How To - Add a Fuse Tap in Your Vehicle

[@RetroCarGuy530]

Additional video on this topic. *Anatomy of An Automotive Fuse Tap* kzbin.info/www/bejne/j3_GYXmcmrFpqNk 🔷Most fuse taps come with a 16 awg or 14 awg wire (smaller wire awg number is a bigger wire which can carry more current) to supply power to the new accessory. The awg wire size / gauge will be a limiting factor as to the max amperage that can be supplied safely via this fuse tap. In most cases, this means a 10 amp fuse is likely to be the maximum fuse amp rating you can use for the new accessory. If the wire from the fuse tap is quite long, the maximum fuse amp rating may be reduced even further. 🔷If you need to add a high amp draw power circuit to supply power to a new accessory, you may want to consider using a fuse tap to supply power to a switched power relay (with a fuse in the relay or in the other power circuit where the relay gets the power for the new accessory). The fuse tap power (switched power or switched with RAP) can supply power to the control side of the new relay. When the fuse tap supplies power to the relay, the relay closes the circuit and the relay then supplies power to the new accessory from the power source the relay is connected to with an appropriately sized fuse and wire awg being used for that power circuit. 🔷At 5:43 in the video I mentioned that you need to have the ignition switch in the appropriate position to make sure it provides the required power type (switched, switched with RAP or unswitched). To find a switched power fuse socket, you must start off with the ignition switch off and locate the candidate fuse sockets that don't have power, then turn on the ignition switch to see if the fuse socket does receive power at that point. If you need a switched power with RAP capabilities fuse socket, you would need to turn off the ignition switch leaving the retained accessory power feature still active and then test the fuse socket again to make sure it was providing that type of power.

[@2006hrk]

Thank you for your suggestions, they are very helpful.. Not only BlackVue B-124X battery pack does not provide Low-profile Mini fuse taps with the battery , but also in the user manual does not talk about as to what gauge of low profile mini fuse tap one should buy separately... There are different websites selling low profile mini fuse taps, but all of them have different awg... for example: BlackVue provided fuse taps(Ato, Micro2 & Mini) have this awg: 14awg 600v 1015 105'c awm other seller #1: 16awg 600v 1015 105'c awm (low profile mini fuse taps) other seller #2: 18awg 600v 1015 105'c awm (low profile mini fuse taps) Gauge - depicts the amounts of load/current a wire can handle safely.. could you tell me, what gauge of a low profile mini fuse tap i should get....out of these three given below 14 gauge fuse tap wire can safely transmit 15-18 amps 16 gauge fuse tap wire can safely transmit 10-13 amps 18 gauge fuse tap wire can safely transmit 7-10 amps In my vehicle's interior fuse box, these are the switched accessory fuses I found.. would you please help locating a fuse that is not critical to the power... can't figure out which one is the right one.. 1) [20A - WIP RR(RearWIndowWiper)], 2) [10A-EPS IG], 3) [15A-WASHER RR(RearWindowWasher)], 4) [20A-WASHER(WinshieldWasher)], 5) [10A-ECU IG NO.3], 6) [10A-HTR-IG(AirConditionSystem)], 7) [7.5A-GUAGE NO.2(Guages&Meters,MultiInformationSystem)], 8) [15A- S-HTR FL(SeatHeaterLeftSide)], 9) [15A- S-HTR FR(SeatHeaterRightSide)], 10) [15A- P/VENT(PowerQuarterWindows)], 11) [7.5A- WIP ECU(WindshieldWiper&RearWindowWiper)], 12) [15A- STRG HTR], Thank You for all your help..

[@RetroCarGuy530]

The wire gauge (awg) governs two factors - amperage it can carry for a particular distance. I would recommend getting the lowest awg value possible. A lower awg number is a thicker wire that can handle higher current loads. Of the three mentioned, the 14 awg can carry the most current/amps for the longest distance. The fuse sockets you listed have a few potential sockets that can be used. Stay away from any fuse socket that supplies power to an "... ECU". The "EPS IG" fuse appears to be for the electric power steering so stay away from that one. Any of the "SeatHeater....." fuse sockets might be a fuse socket that can be used. The "STRG HTR" fuse socket looks like a heated steering wheel so it too is a decent candidate. All of the heater fuse sockets have a 15A fuse in them so the max fuse I would recommend is a 15 amp fuse for the new accessory (B-124X). This is assuming there are no empty fuse sockets available in the fuse box that have switched power.

[@2006hrk]

​@@RetroCarGuy530sorry for bugging you with questions... Just noticed that I Do not have Heated Seats in my vehicle, but there are already fuses(15A fuse in each slots) for them in my interior fuse box. just wondering why these fuses r there when my cloth seats have no such options or buttons to turn them on on my dashboard/instrument panel.. As per your suggestion and as far as the orientation of fuse taps go, S-HTR FL & S-HTR FR are both viable candidate for tapping fuses into them without blocking fuse box cover in the way... Since i have heated seat fuses 15A each & they are not operational (No Current Draw).. so Should I go with 15A fuse(Bottom Slot of the fuse tap) WITH 10A? OR 15A? or 20A? (Top Slot of the fuse taps)... Thank You!!

[@RetroCarGuy530]

Sorry I didn't reply sooner, KZbin doesn't present replies to comments in a manner that is easy to see. If there is a fuse in the fuse socket, it would suggest that something is being powered by the power from that fuse. It is certainly possible that those fuses/fuse sockets are leftovers from a version of that vehicle with the seat heaters. The "safest" approach would be to put the 15A fuse in the bottom slot of the fuse tap and up to a 10A fuse for the new accessory powered by the fuse tap. I like to limit the max draw from a blade fuse style fuse socket to 25 amps (some say 30A is ok). If you're 100 percent sure there is nothing being powered by the pre-existing 15A fuse or fuses, you could simply leave the 15A fuse out of the bottom socket of the fuse tap and you could in theory put up to a 20A fuse in the top slot (if the fuse tap and other wiring to the accessory will support 20 amps). There are three main factors that go into the max fuse amperage size for the new accessory (amperage already supplied by the fuse socket, wire gauge of fuse tap and wiring to the new accessory including its ground wiring and the length of the wiring used for the new accessory). If you haven't watched my FAQ video I created in the past week or so, you might want to check that out where I try to identify the questions / answers that one needs to figure out when trying to size the max fuse amperage size for a fuse tap. kzbin.info/www/bejne/ep-9ZqqYlKZorKc I hope this answers your questions.

[@2006hrk]

@@RetroCarGuy530 Thank you for going extra mile in helping people... very informative youtube video....

[@zacharygillespie-rogers1765]

I watched about 6 videos trying to figure this out before coming here, yours is the one i needed, thank you.

[@PkmHax]

Was about to post exactly this. Thank you!

[@cameronhicks5225]

DITTO! I am trying to wire up a dash cam on my bike and man oh man did this solve my problems and answer my questions!! Thank you so much good sir

[@gowithem]

I watched 1 week of videos, and this video does explains it the best!

[@pkennedy4256]

Finally someone who knows what they're talking about. All the other videos just tell you to slap the add a circuit in.

[@laurensimmons2036]

You really explain how this is done. This is the best video I have seen so far. Others speed through it and don't explain and just waste your time.

[@hahacomm]

The best video explaining how a fuse tap works and what the correct way is to use it. after watching other videos about the fuse tap, this one is the best !

[@johnkrew2163]

YES, this is the video! To all of the people who had already watched several other tutorials on fuse tapping and still have questions. This video will answer all of them👍

[@SilverAura]

This is literally the only video I could find that actually left me feeling confident by the end. The density of knowledge here spares no expense to the thoroughness of it. Thank you, you got me over a major hurdle here.

[@michaeleck1453]

I know this video is a year old now but I wanted to say thank you. I've hardwired many things in the past but never with a "tap a fuse". I hardwired a dash cam with motion sensor and couldn't figure out why it wasn't working. I had one of the "tap a fuse" facing a different direction than the other for wire tidiness reasons. After seeing this video I slapped my forehead. Duh of course the power is only coming from one side or the fuses would be pointless. Thank you for saving my sanity.

[@jaycarpenter9294]

I have watched dozens of videos about fuse taps. Yours is the most concise, logical and easy to understand. Thank you for posting this excellent presentation.

[@Threenineswon20racks]

Damn, finally. I’ve been trying to figure out for days what to do with the lower portion of the fuse tap, since the fuse box socket had no original fuse. Thanks man, great work!

[@nicholaskolomiets2929]

Thanks for explaining the difference between tapping into a fuse that’s already there and tapping into a open slot that may have power and how not to put a fuse in the bottom of using a open slot. I couldn’t really find information on that.

[@RetroCarGuy530]

Glad it helped

[@nps1024]

Yeah, I came here looking for the very same information. Thank you for the useful video.

[@Iw1372]

Finally a professional, all of the other videos they’ll mention “ I’m no mechanic and I’m no electrician”

[@justinmorgan4718]

I too watched multiple videos and multiple web sites with no answer to my questions. THANK YOU , THANK YOU, THANK YOU!!!!!!!!!!! My questions were: 1. Which side is the hot side on a fuse tap. Others glossed over it. You were very precise with pictures and typed out what is what. 2. If I could use only one fuse for the cb add on I wanted to use. 3. That I could use on open slot. And how to use it. Thanks again!

[@mikeb1617]

This is the best tutorial l've ever seen on KZbin.

[@fabparks]

Amazing video. I think most of people (me included) thought the add-a-fuse could go either way while orientation is key. Otherwise you will have both devices on the lower fuse shoulders and likely to blow. My tip to check the orientation (might be easier). Plug the add-a-fuse ONLY with the top fuse inserted (leave the bottom slot empty). Plug it in. If you have 12 output from the red cable you are good. Otherwise you need to twist the add-a-fuse upside down. Once orientation is correct add the bottom fuse if needed. Should make sense.

[@RetroCarGuy530]

This has come up a few times in the comments since I released this video in Dec 2019. I totally agree with your recommendation. I've updated the video's description section with this approach and there's a brief demonstration of this method at 11:00 in the video where I'm testing for power, but that was after testing with the 1/2 fuse. Thanks for the suggestion!

[@staceyreeves9523]

Yup. Easy way to determine which way to plug in.

[@WavyFBaby]

Do you have to put the same type of fuse as the original one? Or can you put a higher rate fuse instead?

[@RetroCarGuy530]

The lower fuse socket in the fuse tap holder is for the original fuse in the fuse box fuse socket (if one is present at all). The upper fuse socket in the fuse tap holder is where the fuse for the new accessory is to be placed. Never install a fuse in the upper fuse socket of the fuse tap that grossly exceeds what the new device/accessory requires. If the new device/accessory only requires 1 amp (or slightly under 1 amp like most dash cameras) then the fuse for the new device/accessory should be in the 2.5 or 3 amp range. The fuse is to protect the circuitry (wires) and the device so never use too large of an amp rating for that fuse. There are 1 amp fuses, but I've found that the precision of 1 amp fuses is not as good as one would hope. A very general rule of thumb is that electrical circuits/wires providing the power to the fuse box fuse sockets have the ability to handle an additional amp load of about 10% more than the fuse in that fuse box fuse socket. That extra capacity is a built in safety margin for those circuits. That means a fuse socket with a 10 amp fuse will most likely be able to handle an additional 10 percent (or 1 amp) of load. For the dash camera example where it can consume up to 1 amp (for the 12-volt supply for the dash camera), you should find a fuse box fuse socket that already has a 10 amp or higher amp fuse in the fuse box fuse socket. That way if both the original device/accessory that is powered by that fuse box fuse socket reaches its full amp draw of 10 amps, there should still be around 1 amp of extra capacity available to handle the extra load of the new device/accessory. If there's a 20 amp fuse box fuse socket and you need 1 amp for the new device/accessory, that leaves a little extra breathing room (capacity) for that circuit. To know if a fuse box fuse socket can provide more than the 10% extra amp load capacity (again a general assumption), you would have to have wiring schematics and knowledge of how power is routed within the fuse box to make an informed decision that more than 10% of the original load was available for the new device/accessory. Without that additional insight into the wiring and fuse box internals, never assume that more than 10 percent of the original fuse amp rating is available for the new device using a fuse tap.

[@heatshield]

I've been collecting info from all sorts of fuse tap install info vids so I can make my own "complete" video to share with a friend. You just took care of that here. I need to do nothing more. I'm sending your video right over to him. Thank you, sir.

[@malikvon4582]

Excellent video, great instruction. Concise and complete. You obviously not only know your craft but also how to teach it. I wish more did.

[@princetonjohnson5826]

Best video about this and it’s not even close! You’ve earned my like and subscription for prompt responses to ALL of your viewers you really are amazing

[@RetroCarGuy530]

Thank you so much!

[@Caprica-Approaches]

Wow - awesome, thank you. Showed me so much I desperately needed, to add power for HF radio w/o going through firewall or ripping apart the interior fuse box :-)

[@camdlux]

You addressed EVERY question I had as I prepare to add accessories to my Jeep. Thank you.

[@AbyssalTenacity]

Most helpful comprehensive video for my hardwire project!

[@RetroCarGuy530]

Glad you liked it!

Hi i love the video. Very informative. I have a project that id like to do that i didnt know i needed to do. After buying 2 led lighted usb cables to use for powering my phones from connections in my center console. I learned that unlike the usb port, which shuts power when ignition is off.. my center consoled 12v cigarette lighter does not.. power continues to flow to the 12v cigarette lighter so im looking to somehow get my 12v cigarette lighter shut off when the ignition is off... Kinda like the usb port does. Any suggestions on how to do this specifically? Any videos thst covers this particular prroblem? I saw a video using a AAF holder and 2 fuses in an ignition switched socket and the AAF holder wire going to the the 12v unswitched socket tapped using that sliver of metal taped/shrink wrapped to a broken or blown fuse. Not sure if this is safe or correct and if it is not sure what side the metal silver tap connected to the burnt/broken fuse in the unswitched 12v socket .. the hot side or the unpowered side? Any help/advise would be greatly appreciated

[@RetroCarGuy530]

You can achieve something like you want using one of two methods. Both methods require the same method of sourcing power from the fuse box fuse socket that has switched/accessory power. Sourcing Switched/Accessory Power: I would suggest finding a fuse box fuse socket with a 15 to 30 amp fuse in it already to act as the power source. You don't want to overload the fuse box fuse socket that is providing the power so make sure the original power load of the fuse box fuse socket and the additional load for the two LED lighted USB cables will not exceed the capacity of that fuse box fuse socket. Pick a fuse box fuse socket that does not provide power to a critical system or module in the car. You place the original fuse box fuse into the lower fuse socket of the fuse tap and the upper fuse socket of the fuse tap would have a fuse sized appropriately to the power required for the two LED lighted power cables Option One - Sending Power to Fuse Socket For Cigarette Lighter: You could connect the wires of the first fuse tap providing the power to a second fuse tap sending the power to the cigarette lighter socket. The power coming in the wire on the second fuse tap would be sent through the upper fuse in that fuse tap and down the left leg of the fuse tap. You would leave the bottom fuse socket of this fuse tap empty. You must identify the side of the fuse box fuse socket that does not have power and that's the side of the fuse socket you plug the left leg of the second fuse tap. Option Two - Sending Power to Fuse Socket For Cigarette Lighter: Instead of using a second fuse tap as noted in option one, you would find a male spade connector of the correct size that matches the thickness/width of the style of fuses used in the fuse box. You would connect the male spade connector to the wire coming out of the first fuse tap. You would insert that male spade connector to the side of the fuse box fuse socket for the cigarette lighter socket that does not have power. The power provided by the first fuse tap will be fed to the cigarette lighter socket.

​​​@@RetroCarGuy530​hi sorry for the delay in responding. But based on my learning and understanding from KZbin videos and your very precise instructions I still wasn't able to get this to work. Here is my 2023 Mazda cx5 fuse box layout. 3rd down top left is 25a 12v label. From another video I saw using 2016 Mazda cx5 the fuse box layout was somewhat similar (12v 3rd down from top left) and he selected the bottom most fuse to tap (switched fuse) this is his video. kzbin.info/www/bejne/fIPdaaGNorypppIsi=LcldBJa8JidShO1A Since the fuse box layouts were somewhat similar (except the fuses have increased was 15a & 7.5a back in 2016 now my 2023 Mazda it's 25a & 15a) I used the same "UTILITY" fuse socket which is "SWITCHED" to insert/house the fuse tap holder with the orig 15a fuse in the bottom slot and a 25a fuse in the top slot adjacent to the wire. Ran the wire to the "UNSWITCHED" cigarette lighter fuse socket (3rd down from the top on left) and inserted into the cigarette lighter fuse socket (3rd down from top left) a male Spade connector along with a live un-blown 25a fuse into the side of the fuse socket that does not have power. My result no change.. still with the engine off ... Lighted USB phone charging cable remains illuminated and does not turn off as I would hope. I'm not sure if I followed your instructions precisely enough but it seems to me (as a non electrical guy) that the male Spade wedged into the non-powered side of the cigarette lighter fuse socket can't due what it's intended to do (get power) from the alternate fuse box socket so long as the 25a fuse in the cigarette lighter fuse box socket is live/not blown/not-broken etc. Am I missing something in your instructions? Please advise P.S. I sent you a pic of my car fusebox layout via DM on IG. And just as an FYI.. I believe I tried to follow your option#2

Thank you so much! I want to thank you again for all your help. You were right and I have only you to thank for finding me the interior fuse box layout guide that you sent me.. that along with your comprehensive, logical, very detailed and knowledgeable instructions I was able to get the project done ! YAY. Fuse #9 was the one under the ac under the dashboard that shuts off with the ignition and #11 was the 1st rear cigarette lighter (center glove compartment) the one I was trying to fix that was UNSWITCHED. I put the tap on #9 with the hot side on the correct leg and male Spade connector on non power side of fuse #11 and it all worked. Thank you again for finding that fusebox socket guide and sending it to me. Your the best! .

[@TrainerDude51]

FINALLY! Someone explained it and detailed it so I can understand! Thank you!

[@2000S10V6]

I've never used a fuse tap and just assumed you would just plug it in and go but I never thought about orienting it for the power to always go through the fuse for the fuse to do its job. Makes perfect sense. I'm glad I watched this video.

[@mariochang4924]

Absolutely the best tutorial video about hardwiring a dash camera. Saved me a lot of time and more importantly not burning up my device. Thank you.

[@RetroCarGuy530]

Glad it helped!

[@hawaiiantimes7702]

Great tip on cutting the fuse in half so the multimeter can get a read.

[@YezR909]

Finally someone who explained it where I can understand and went into depth. Thanks.

[@RetroCarGuy530]

I'm glad it was helpful!

[@thebonkarsgamer449]

Honestly that was such a well explained video

[@bobadams1696]

Good video. I appreciate the accurate language, definitions, and clarity.

[@Dssan0905]

Thank You! After watching the product I am installing and reading reviews, your video tied it all together

[@casterlau999999]

by far the most informative video, the visual demonstration is easy to follow (everything focuses correctly!) for beginners like me. Thank you so much for teaching!

[@RustyNord]

This was so much clearer than any diagram or video I could find. I now feel confident I can install my dash cam and have it wired properly for safety. Thank you.

[@RetroCarGuy530]

I'm glad it helped. There are a couple of different trains of thought on this topic of using a fuse tap to obtain power for a new device/accessory. What I demonstrate in this video is the "in parallel" approach of routing the power through the fuse tap. The power obtained from the fuse box fuse socket is directly routed to both the lower and upper fuse sockets in the fuse tap. There's another approach which would be labeled "in series" power routing approach. That's where the power from the fuse box fuse socket goes up the right leg of the fuse tap, through the lower fuse in the fuse tap and then down the left leg of the fuse tap to the original fuse box fuse socket and it also goes then up to the fuse tap's upper fuse socket. All of the power load runs through the lower fuse in the fuse tap. Which approach is best to use will result in spirited discussion/debates. The "in series" power routing method can be seen as the absolute safest approach, but it may also lead to blowing the original fuse in the lower fuse tap fuse socket since both power loads are being run through the lower fuse. For dash cameras, radar detectors and similar power demanding devices (usually 2 amps and very often dash cameras use less than 1 amp), the "in parallel" power routing approach is very safe. It will only be adding 2 or often less than 1 amp to the circuit that is supplying the power to the fuse box fuse socket. Thanks for checking out this video! I have another video that tries to explain the "in parallel" approach a little more in depth. kzbin.info/www/bejne/j3_GYXmcmrFpqNk

[@k.zekeswaringen2122]

Appreciate your explanation on fuse taps ! I am currently hard wiring dash cams on a couple of cars - one has an empty slot with power, the other one - I will have to pull the fuse, add the tap & reinsert the original & accessory fuse. I had no idea about the order these fuses went in - until watching your fine tutorial. Thanks again !!!

[@Ratlins9]

What a superb video. Great step by step explanations with detailed close ups of the procedures needed to perform this task. Thank you for sharing your knowledge. This helped me.

[@B58Hustler]

This is far and away the best video on YT for this subject - well done!

[@RetroCarGuy530]

I'm glad you found it helpful!

[@frkids8401]

the best video on youtube about fuse tap, even for me who doesn't really understand english. thank you very much !

[@RetroCarGuy530]

You are welcome!

[@dontknowyet726]

So well done. Makes the entire process so much easier to understand. Thank you Sir!

[@RetroCarGuy530]

You're very welcome!

[@InvertChaos3]

Super helpful explanation of how to determine which side of the fuse slot has 12v to make sure the tap is oriented correctly. I also learned that fuses have the exposed metal on too for probing. I have never noticed that before!

[@RetroCarGuy530]

Glad it helped

[@DamianMasters]

GREAT video!! Quick question.. can i tap into my fuel pump fuse to 'tap' into it with my aftermarket amplifier?

[@RetroCarGuy530]

I would suggest to not use the fuel pump fuse for an amplifier (or any other accessory). Why I say that is the fuel pump is a critical system of your vehicle and I recommend against using a fuse tap in a socket that is obtaining its power from a module, sending its power to a module or critical system. This is to be a as safe as possible to not introduce a problem by adding a fuse tap to the circuits for those types of critical systems. I would also assume the amplifier might pull a non trivial amount of amps as well. In my FAQ video, I discuss more in depth about my 25 amp maximum for the original max power draw (fuse amp rating) along with the amps for the new accessory. This is the link to that FAQ video: kzbin.info/www/bejne/ep-9ZqqYlKZorKc

[@bentnickel7487]

I'm as slow as molasses, when it comes to Algebra and electronics, but the way you explain the steps, it seems I learn more from you than any other KZbin channel, therefore I've subscribed. Good luck on teaching this old man, a new subject.

[@RetroCarGuy530]

I'm glad you found the video helpful. If you haven't already watched the FAQ video I made last summer on this topic, it might be worth the time to take a look at that video as well. kzbin.info/www/bejne/ep-9ZqqYlKZorKc

[@craigerickson1910]

Rather than cut a fuse in half to create a tiny test probe, why not purposely blow a fuse of any amperage you have on hand you're willing to sacrifice by shorting it on the car battery? Now you won't need to cut the fuse in half and it'll be easier to plug in because it's normal size so you can use the fuse puller to remove. Plus you only need to plug it in once. Both metal taps on the top of the fuse are now accessible for testing. Good video, Explains well how fuse taps work and how to properly hook them up.

[@17shakil]

Thanks a lot, some people are masters of teachings, you are one of them!!

[@RetroCarGuy530]

So nice of you to say that.

[@JaySpecimen]

What’s the setting on the reader to test the fuses? I just got one but I don’t understand anything on that dial 🙃

[@RetroCarGuy530]

To test for power like I do in the video, you select DC Volts. To test a fuse (not in the fuse socket) to see if it's "good", select Ohms/Continuity.

[@captainwho1]

Thanks for a great video and for taking the time. I need to add a fuse tap to supply as much as 20A to a power window circuit. I will be abandoning the original wire because it has an open. Where can I get a fuse tap that is rated for up to 20A for the add on circuit because all I seem to be able to find are ones with a #16awg wire and 10A maximum rating? I guess I'd need one with a #14awg wire? Thank you.

[@RetroCarGuy530]

The blade style fuse taps that I can find all have 16 awg or at best 14 awg wire. One fuse tap with 14 awg claims to support up to 30 amps, but that would only be for short distances (4 feet or less). Some research I did a while back about wire gauge and max amp loads suggested that a 14 awg wire could carry 20 amps for up to 6 feet. A 12 awg wire could carry 20 amps for up to 10 feet and a 10 awg wire could carry 20 amps for up 14 feet. It also depends on what fuse type you need, but here's an affiliate link of mine to a ATM/Mini fuse tap with 14 awg wire: amzn.to/3CyTLKY There are inline fuse holders with 10 awg and 12 awg, but you'll need to source the power (I assume switched / accessory power) for that from a relay. Although, finding a relay wiring pigtail with thicker wire is difficult too. The relays usually can support up to 30 amps, but the wiring pigtails tend to have 16 or 14 awg wires as well. I wish I could help with a specific solution to your question. I hope this helps in some way.

[@mikeestrada933]

@@RetroCarGuy530 So it wouldn't be a good idea to connect a 12 gauge wire running 10 amps into one of these 16 or 14 gauge wire taps?

[@RetroCarGuy530]

@@mikeestrada933 the limiting factor is the 16 or 14 awg wire from the fuse tap as well as making sure the fuse socket the fuse tap is plugged into can provide the 10 amps required. If the length of the entire wire run from the fuse tap to the device and from the device through its ground wire (yes including the ground wire) is no more than 6 feet (16 awg fuse tap wire) or 12 feet (14 awg fuse tap wire), then in my opinion you should be able to do it. The 6 feet (16 awg fuse tap wire) and 12 feet (14 awg fuse tap wire) are the max lengths that a circuit made up entirely of that wire gauge should be able to handle 10 amps based on some very conservative electrical automotive wire amperage charts I've used in the past. I'm not a fan of using a thicker wire in part of a circuit than the thinnest wire in that circuit. It gives anyone that comes after you the impression the entire circuit is made up of that thicker gauge wire which will give the false impression that the circuit could potentially handle more amps than it truly can.

[@mikeestrada933]

@@RetroCarGuy530 Okay thank you! I ask because the kit i bought has a 12awg wire installed that has to be powered by a switched ignition source

[@RetroCarGuy530]

If a device requires 10 amps to operate, that's the power level I start thinking about using a relay to power the new accessory. A fuse tap is a great way to get power to operate circuits that don't demand to much more from the circuit the fuse tap is plugged into in the fuse box. Here's another approach you might want to consider: A four terminal relay can be used to supply switched ignition power as well. Relay terminal #30 of the relay would be connected directly to the vehicle's battery with an inline 10 amp fuse (in this example) to protect that circuit. Relay terminal #87 would be connected to the new accessory to supply the power to the new device/accessory. Relay terminals #85 and #86 are used to control the relay (on / off). A fuse tap can be used to source the switched power to control the relay. The power required to power the control side of relay is usually well under 1 amp making it an excellent candidate for being used with a fuse tap power source to run the control side of the relay. Most relay wiring charts show terminal #86 is connected to the switched power source (from the fuse tap) and terminal #85 is connected to ground. This moves the higher power demand for the new device/accessory directly to the battery (using proper gauge wire and inline fuse) and the power demands on the fuse box power circuit the fuse tap is installed into is very minimal. I've used the relay wiring approach when I've installed dash camera battery packs into my vehicles. One of them requires 9 amps (directly wired to the car) or 5 amps when using the power port adapter. To allow it to charge more quickly, I hardwire the power input for the dash camera battery pack, but I use a four terminal relay to supply that power.

[@mnmstudiosoc]

Thank you for the informative video. I have one dumb question...where is your black probe connected from your multimeter when testing for available power?

[@RetroCarGuy530]

You connect the black probe / ground connector to an available ground point or a bolt / screw connected to the body of the vehicle or bare piece of metal and that should give you a grounding point for the test.

[@mnmstudiosoc]

@@RetroCarGuy530 Thanks for the quick reply!

[@johnnyflores100]

Very good video. I don't know anything about electrical and I used a lot of points in this tutorial to install my underglow kit today. Thank you! No more Rocker Switches.

[@RetroCarGuy530]

Glad it was helpful!

[@Tubedyou13]

Super helpful. Thank you very much! Needed this explanation to udate the stereo in my car.

[@SC-rb2jr]

Excellent video. Lots of videos out there don't tell you that it matters which way round the fuse tap is plugged in.

[@blinko656]

This is a well done video. Thought out well and is very easy to understand. I have a Amp for a speaker system. I went into it to make a few gain adjustments and found that the Alpin light on the Amp has been on, charged, for 6 years. I did find the proper fuse that only foes on when the ignition is turned on. all is well now. TY. Never knew they had piggy back fuses ...:)

[@RetroCarGuy530]

Thanks! I'm glad you found the information helpful in solving your amp's power issue.

[@eb6736]

Thank you for this. Was trying to install a hardwire for a dashcam in the interior fuse box of a 2022 honda accord and I have blown 2 multi block fuses when just using a test light probe to find which side the power was on. The second time I was very careful, but once I touch one side of the contact, it arced. Not sure what I'm doing wrong but I like the idea of using the half fuse for a testing.

[@azclaimjumper]

Please recommend - a link to a Fuse Tap Kit 4:52; the diagram now makes it clear to me how things should go. I've created a screen shot of the diagram on my computer for future reference & printed out the screenshot. I'm considering hard-wiring a dashcam. Yes, I've subscribed & rang the notification bell. Warm Regards from Reno, Nevada

[@RetroCarGuy530]

I'm glad you found the video helpful. There are a large number of fuse taps available, that I don't have one particular one/brand to suggest. If you search Amazon you should find some for your purpose. Just make sure you know what fuse type your fuse box contains, so you know the correct type of fuse tap to purchase.

[@tai2523]

Perfect video! I only run into the issue of the added fuse NOT fitting into the housing before I place it into the fuse box. It just doesn’t want to go in no matter how hard I try and it’s been confirmed to be the correct one

[@RetroCarGuy530]

If I understand you correctly, the fuse that plugs into the top slot of the fuse tap is not fitting (the fuse for the new accessory)? I've seen some fuse taps of lower quality that have a variation in their compliance with the size specifications for the fuse type they're to support. The only thing I could suggest is getting another fuse tap of the same type from a different company/seller. The fuse should fit snugly into the socket for it, but it should not be overly tight preventing you from inserting the fuse into the socket.

[@michaeldefrancesco5885]

The best description and detailed explanation I have found to add an accessory switch for my vehicle. TY

[@RetroCarGuy530]

Awesome, thank you!

[@blakegilliam8223]

Finally someone who knows how to give a presentation

[@bobbartlett3979]

Very good. Very professional. Visually steady and clear. Thanks!

[@thecavemanlibertine2738]

Clear and concise...well done and keep up the good work. Greetings from England

[@jimsego]

Thanks for taking the time to make this great video.

[@vj8452]

Thanks for teh good and detailed video! But i haev one question: the "add a fuse" only provides power, so i still would haev to connect my device with the negative to the nearest ground (or earth). i want to install an auxillary digital clock besides my cigarette lighter, so could i just use the existing ground on that, when i am also tapping into the cigarette´s fuse? i hope i could explain my problem clearly. Thank you already! Greetings

[@RetroCarGuy530]

Correct, the fuse tap only provides the power to the new device/accessory. You will need to connect the device's ground wire to a good ground location to complete the entire power circuit.

[@MarcusLeonard307]

Excellent video and the best and direct explanations I've seen on this topic.

[@nelsonechemendia2063]

Great info on this video. many thanks! Question: Are there any available tapping fixtures for J-case and M-case cartridge female terminal fuses? Thanks again.

[@RetroCarGuy530]

I have not come across any J-Case or M-Case fuse taps. If the accessory's power demands are beyond that of a blade style fuse and fuse tap, then you might consider using a blade fuse tap to supply the control circuit power to a relay that would then supply power of sufficient amperage to the accessory.

[@nelsonechemendia2063]

@@RetroCarGuy530 Thanks so much for your quick response. I'm gonna try to AC compressor relay. Seems all fuse points are all time hot in my truck (2017 F150 lariat). Haven't tried w relays so far but i see no other option. Thanks again.

[@randdylopez1994]

Thank you sir just did my installation and became great because of you!!!

[@RetroCarGuy530]

Glad I could help

[@whatworkedforme]

A great example of testing and procedure. Hi from England 👍👍

[@ryshaystudio77]

Thank you for explaining so anyone can do it! Very informative!

[@digidandan]

The best tutorial regarding the fuse tapping ! Thanks a lot 🙏

[@liamhilt1822]

Thank you sir. Why this wasn't the first recommend video I'm not sure. You answered everything clear and concisely.

[@RetroCarGuy530]

Glad it was helpful!

[@montealegre_rp]

BEST FUSE TAPE VIDEO IN KZbin!

[@Convertibenz]

excellent! complete and concise info on what i'm trying to work on. that half a fuse trick is good.

[@RetroCarGuy530]

Glad you liked it! I show an alternative approach in another fuse tap video on my channel where I use the entire fuse in the upper fuse tap fuse socket. kzbin.info/www/bejne/j3_GYXmcmrFpqNk

[@onetime5640]

Best video yet , thank you !

[@Lancelot_Jago]

Thank you. You have cleared up most of my questions but two. 1. How do you know the wiring behind the fuse socket can sufficiently carry the current for both devices? 2. If you happen to find an active empty position, again, how can you be sure you will not overload the wiring there? Thanks again. Lance

[@RetroCarGuy530]

The power bar that blade style fuse connects to on the back side of the fuse socket (inside of the fuse box) are capable of carrying a decent amount of current/amperage. There are times that even the vehicle manufacturer will overtax the current draw on the power bar for a portion of a fuse box. I had a 2012 Dodge Charger SRT8 that had just that situation and FCA issued a recall to have a couple of fuses / circuits moved from one fuse bar to a different fuse bar within the fuse box. The only sure way to not exceed the available power on the fuse bar(s) within the fuse box sockets is to have a full understanding of which fuse sockets are tied to which fuse bars within the fuse box and how many amps are available on each fuse bar. That is not something that is usually available from a vehicle manufacturer. Most (if not all) vehicle manufacturers will not look favorably on the customer adding a fuse tap to any fuse socket in the vehicle. That's why I strongly suggest that the fuse socket must source its power directly from the battery or from a switched battery power source to be assured of sufficient power. It is possible that a fuse socket in a fuse box can obtain its power from a module within the vehicle (like the body control module - BCM). You don't want to select a fuse socket that is sourced from a module or supplies power to a module since those type of fuse sockets will often be sensitive to the amount of power present or consumed via that fuse socket. For example, the BCM provides power to a large number of items / accessories in the vehicle like the interior lights of the passenger compartment. There will be a fuse in a fuse box (likely inside of the passenger compartment) for those items that receive power from the BCM. Adding a fuse tap to a fuse socket that sources its power from the BCM, may place too much of a load on that circuit from the BCM and it may cause issues with the thing being powered by the BCM or the BCM itself. A fuse tap is also limited in the amount of amps it can safely supply as well since the wire gauge (awg) of the wire coming out from the fuse tap will often be limited to 10 to 15 amps max. Blade style fuses range in amp ratings from 1 amp to 30 amps. Fuse sockets that need to supply more amps are often a different style of fuse (not a blade style fuse). I have a follow up FAQ video that tries to discuss some of these questions. kzbin.info/www/bejne/ep-9ZqqYlKZorKc I hope that helps.

[@adamchandler6987]

After installing a fuse tap do you ground the black wire for your accessory off to the car?

[@RetroCarGuy530]

Yes you do!

[@adamchandler6987]

@@RetroCarGuy530 thank you 😊👍

[@DavidWilson-ps8gx]

Hello a great video however, you did not mentioned how your decided what amperage of fuse to use in the slot that had no fuse. I know if you are tapping into a fuse socket with a fuse you must add a fuse of equal amperage. But no one has indicated when there is no fuse how do you decide what amperage fuse to use. Thank you

[@RetroCarGuy530]

The "you must use a fuse of equal amperage in the fuse tap as the original fuse in the fuse box fuse socket" is not as true as one might think. You never [never] want to add a 20 amp fuse via a fuse tape to a pre-existing circuit/fuse box fuse socket that already has a 20 amp fuse. Why, you're potentially asking the wiring in the fuse box itself or the wiring providing power from the car to provide up to 40 amps if both circuits (original + newly added via the fuse tap) require their max power amount. As I showed in my video, supplying power to the left leg of the fuse tap allows power from the fuse box to be supplied to both the lower fuse [original fuse box fuse] and the new device's fuse [fuse in upper fuse tap fuse socket]. This is the "in-parallel" method of routing power in the fuse tap. This potentially allows up to 40 amps to be sourced from the fuse box fuse socket and the wiring that provides power to that fuse box fuse socket. The other power routing approach using a fuse tap [in-series] is to supply power to the right leg of the fuse tap. That routes the power up the right leg of the fuse tap, through the bottom fuse to the left side/leg of the fuse tap. The left side of the fuse tap will send power up to the new fuse for the new device and down the left leg to the fuse box fuse socket for the original circuit. This is the "safest" approach since the bottom fuse will be the limiting factor as to how much power is allowed to be sourced from the fuse box fuse socket. The downside of this approach is that when an over amp condition exists, the bottom fuse in the fuse tap will blow and you'll lose power not only to the new device, but also to the original circuit that the fuse box fuse socket supplies power to in the vehicle. Using the "in-parallel" power routing approach, I typically recommend that if a fuse socket has a fuse in it already, you can somewhat safely assume there is at least a 10% amount of extra [available] capacity in the circuit/wires providing power to that fuse box fuse socket. A 10 amp fuse in the fuse box fuse socket would mean you could add a 1 amp new load. A 20 amp fuse in the fuse box fuse socket would mean you could add up to 2 amps new load on the circuit. If you have more detailed knowledge of the internals of the fuse box itself and if the fuse box fuse socket sources its power from a bus bar (metal bar supplying power to multiple fuse box fuse sockets) you can then "safely" add a new fuse [in-parallel power routing] via a fuse tap with a higher amp rating than the 10% rule-of-thumb I'm suggesting. If you don't know how power is provided to the fuse box fuse socket [most people don't have access to that type of detailed info], I strongly suggest you use the more conservative approach I'm suggesting of 10% of pre-existing fuse in the fuse box fuse socket. Adding devices such as dash cameras and radar detectors is a very safe thing to do since their amp draw is usually around 1 amp [at most]. Sourcing power for a dash camera battery pack via a fuse tap is not something I recommend since those devices can consume up to 10 or sometimes 13 [peak draw] amps. For devices that consume 5 amps or more, I strongly suggest using a different approach to source their power. In my opinion, higher amp devices should source their power directly from the vehicle's 12V battery with an inline fuse near the battery. If the new device requires switched/accessory power, you can still source the power for the device from the vehicle's 12V battery [like I stated above], but add a 4-pin relay that will turn that power on/off based on switched/accessory power sourced from a fuse tap in the fuse box. Relay pin 30 would be connected to the wire coming from the battery / inline fuse. Pin 87 would be connected to the 12V wire going to the new device/accessory. The amount of power that a relay's control circuit [pin 85 & 86 - see relay's documentation] consumes is between 100 mA (0.1 amps) and 150 mA (0.15 amps) which is well within the margin of "safety" I mentioned for using a fuse tap to source power from a fuse box fuse socket.

[@RealeaD]

thanks. most informative out of several videos I have seen

[@cynthiajohnson7039]

what is the black lead attached to when testing the fuse to determine the power input. Could not see from the video. Thks

[@RetroCarGuy530]

The negative (black) test lead is connected to a vehicle ground or negative battery terminal. In my test setup, I used an DC power supply. The negative wires from the test light and the multimeter were connected to the negative on the 12-volt power supply.

[@2jader1]

After overwhelmed videos I watched before I got here took a break and I came back to this one and totally understood the leguage he is really good

[@RetroCarGuy530]

I'm glad you found the video helpful!

[@prodigy6000]

Good Vid but, the one question to ask is what is the amp value behind the panel that feeds that circuit ...for light stuff you'll be ok, but if you want to supply a sub panel you need 30A and i don't think any of these taps will handle more than 10A....newer vehicles TIPMs have sensitive solid state boards in the PDP making issues worse. I like to always in stall 2 fused sub panels one full/hot and one run/Acc, this makes future add-ons a breeze, but it needs to be done properly.

[@GozieZilla]

The best explanation video I've seen on KZbin. I subscribed thank you

[@callmebackfriday2]

Thanks for explaining it in a very simple term which I can understand. Excellent Video. A+

[@RetroCarGuy530]

Glad it was helpful. Live long and prosper!

[@philippecapraro5766]

Great video. Quick question? Is there fuse boxes that will not accept fuse taps. I have read that certain modular fuse boxes will not accept fuse taps. If so what do I do next?

[@RetroCarGuy530]

I've not personally seen a car fuse box that doesn't at least have a few blade style fuse sockets. There are the traditional two leg blade fuse sockets and some newer cars have three leg (Micro3/ATL) fuse sockets. There are Micro3/ATL fuse taps available for those situations. Otherwise, you may need to run a wire with an inline fuse from the car's battery to source power for a new device/accessory. If it needs to be switched power, then the wire from the battery can feed a 4-terminal relay, but the control side of the relay would need to get a switched power source to drive the control side of the relay.

[@bostonrules545]

Wonderful video. I have a question. My accessory (lights) came with a fuse tap and 15a fuse. I've located an empty fuse spot in the cabin that has the correct switched power but I'm worried if I should get a new 10a fuse for the accessory since you recommended not to exceed 10a. Lights are LED so should run minimal power. Also, do you need to worry about how much power is going to the empty fuse spot VS the fuse im plugging in? Sorry for novice questions.

[@RetroCarGuy530]

I've seen accessories supplied with fuses that have an amp rating far too large for the accessory's true runtime needs. There are two amp draw levels of interest, the inrush amps when the accessory is first turned on and then the steady state amps it draws during its regular use. The wiring the provides power to the fuse box fuse socket that you want to use is something of a concern as well. LED lights should have a somewhat reduced amp draw. If the product documentation shows the max amps it will draw, that's the first thing to check. The next / best way to check the max amp draw is to use a DC power supply with a digital display showing the amp draw or use an inline multimeter to monitor the amp draw or a multimeter with an amp clamp to monitor the amp draw. Whatever the max amp draw is for the device, you would want to add 1 or 2 amps to that value and that is the amp rating for the fuse to use for the new device/accessory. Having a fuse that has an amp rating well above the actual needs of the device/accessory isn't protecting it very well unless there's a dead short to ground. Fuse taps are very good ways to obtain power for low power consumption devices (dash cameras, radar detectors or similar devices : 1 to 2 amp range). When the new accessory/device starts to draw 5 to 10 amps that you might still be able to use a fuse tap, but as I get older I'm getting more conservative with my statement of how many amps can be obtained to power a new device/accessory. My current opinion for a new device is that if it draws 5 amps (10 amps was my previous level) or less, then a fuse tap is a decent way to power it. If you need 5 amps or more for the new device/accessory then obtaining power directly from the vehicle's battery with an inline fuse is the best approach (IMO). If you need accessory/switched power, you can use a 4-pin relay to provide that power. You would use a fuse tap to get accessory/switched power to control the relay. A relay only consumes 120 to 180 mA for the control feature of the relay.

[@bostonrules545]

@@RetroCarGuy530 thank you so much for the thoughtful and informative response!

[@qqkthxbye]

Does the fuse itself have to be inserted a certain way? Or either way will be fine?

[@RetroCarGuy530]

The fuses can be inserted in either direction in the fuse tap. The fuse tap is the only part that requires that it be inserted into the fuse socket in the correct direction. It's very important to get the power from the fuse socket supplied to the left leg of the fuse tap since that is the side of the fuse tap that supplies power directly to both fuse sockets within the fuse tap.

[@osvaldoyepez7824]

What fuse you recommend to tap to connect fog lights

[@RetroCarGuy530]

That has a few different facets to the answer. The total amp draw for the fog lights needs to be known. Depending on the types of lights used in the fog lights, it could only take a couple of amps up to nearly 10 amps (with incandescent bulbs). A fuse box fuse socket that supplies power to critical components (any modules that control the engine, transmission, air bags, body control module, etc) should be avoided. Fuse box fuse sockets that get their power from any of the vehicle modules should be avoided as well (circuits that are turned on/powered by modules like the body control module). Adding a large amp load to a pre-existing circuit is not advisable since the wiring that provides power to/from the fuse box fuse socket may not be able to support a large additional amp load over the already existing load placed on that circuit. You may want to consider using a 4-pin relay to supply power to the new fog lights. The power source for the circuit (load side) would be sourced directly from the vehicle's battery with an inline fuse (pin 30 gets power from the battery, pin 87 sends power to the new device/feature). The control side of the relay (usually with pins 85 [ground] / 86 [control power]) can use a fuse tap to source the switched accessory power from a fuse box fuse socket or from a on/off switch to control when the fog lights are on/off. I address this topic in a video I created to review dash camera battery packs which can demand a large amp draw as well. I mention / show the relay approach in this video kzbin.info/www/bejne/fZ-WeqJ4n7SSjMk

[@6xcchamber971]

I need to power up a standalone engine harness I believe needs to be key/on power. if adding a fuse tap such as this, what amp fuse would you recommend? I was told by a mechanic that I should use a 50 amp fuse in the cars existing fuse block to tap into it. What are your thoughts on this? Thank you I have learned from your video!

[@RetroCarGuy530]

A fuse tap should only be used to provide power to devices which require under 10 amps and in many causes I suggest under 5 amps. The reason for that is you have to be conservative in your assumption of the amount of available power on any given circuit providing power to the fuse box fuse socket. I provided a similar answer (with more details) recently in another viewer's comment post. I would recommend sourcing the power for your new harness directly from the vehicle battery with an inline fuse that will protect the new circuit. Use a 4-terminal relay to control the on/off status of the relay. From that other comment reply: This topic requires a somewhat complicated answer. Without detailed/specific knowledge of how each fuse box fuse socket obtains its power and what the max amp rating is for the source of power, there's no perfect way to answer this question accurately. The wiring / method the power is provided to the fuse box fuse socket must be able to provide the original amp load and with most situations it has at least a small amount of built-in "extra" amp load carrying capacity. That "small amount" is usually around 10% of the original amp load rating. 10 amp = about 1 amp extra. 20 amp = 2 amps extra. Is this a perfect way of estimating the amount of available amps, no, but it is a fairly safe assumption. If the device needing power from a fuse tap requires a large number of amps (over 5 amps) to start/run, I would not recommend a fuse tap for its power source. For devices with higher amp load requirements, sourcing power directly from the vehicle's battery with an inline fuse to protect that circuit makes more sense. If the device requires switched/accessory power, I would still source the new device's power from the battery with an inline fuse, but use a 4-terminal relay to toggle the power on/off. You could use a fuse tap to source the switched/accessory power to turn on/off the control side of the relay if you want it to turn on/off with the ignition switch. If you want to manually control the on/off behavior with a toggle switch, you would use that to power the control side of the relay. I have a video discussing the "relay" approach to power a dash camera battery pack. kzbin.info/www/bejne/gKDEYZmfgL-MY9E I recently posted on a DashCamTalk website about the differences in the installation of a fuse tap into a fuse socket (power on the left leg vs power on the right leg) here. dashcamtalk.com/forum/threads/a229-pro-2ch-issue-with-power-or-hardwire-kit.50021/post-607344

[@6xcchamber971]

Thank you for your time it is very much appreciated!@@RetroCarGuy530

[@freerangechickenman054]

My Silverado does not have a sunroof, but has a 25 amp fuse in location marked sunroof. could this be a viable place to use a fuse tap? I'm trying to use the tap as a power source for my mobile ham radio. I was also wondering if a 10 amp fuse would be a good choice for that. It's a Midland MXT400, which is a 40 watt transceiver, or would a lower amp fuse be better. Thanks, glad I found your channel

[@RetroCarGuy530]

You should be able to use an unused fuse box fuse socket that is normally rated for 25 amps if the feature is not present in the vehicle. Make sure you only use one fuse in the fuse tap (upper socket). Placing any fuse in the lower fuse socket of the fuse tap, might provide power to something in the vehicle that is not intended to receive power in your vehicle's configuration. It doesn't necessarily cause a problem in most situations, but to be 100 percent sure, only use the one fuse in the upper fuse socket of the fuse tap. I would think a 10 amp fuse would be sufficient for your ham radio, but you need to see if there are any specifications documented on the unit or in its product documentation that states how much power it draws while in use and while powering on.

[@freerangechickenman054]

@@RetroCarGuy530 Thanks for the quick reply. You're my new hero.

[@logankey7978]

Great and Fantastic Tutorial. Much appreciated.

[@RetroCarGuy530]

Glad it was helpful!

[@hj7993]

Great video and explanation 👍. Instead of cutting a fue, you can use the fuse tap without installed fues to check for power as the metal leads reachable.

[@RetroCarGuy530]

I have a statement in the video description's section about using the fuse tap with a fuse installed only in the top fuse socket to check for power. 🔷Another "easier" way to test for fuse socket power and avoid using the 1/2 fuse testing approach is to use the fuse tap itself with a fuse in the top fuse socket of the fuse tap. In this approach, you test for power by inserting the fuse tap and then checking for power at the end of the red wire coming out of the fuse tap (as shown at 11:00 in the video). If you don't have power with the fuse tap in that position, rotate the fuse tap 180 degrees and test again. Once you find the correct orientation for the fuse tap in the fuse socket, you can install the original fuse from the fuse box fuse socket in the lower fuse socket of the fuse tap. If there was no fuse in the fuse box fuse socket then you should not have any fuse in the lower fuse socket of the fuse tap.

[@hj7993]

@RetroCarGuy530 Thanks a lot for the info. In fact, this idea is much better. Great Work 👍.

[@PouyaLucky]

Excellent and informative and very fine details ... what a guy, awesome content like Scotty but with much less shouting 😂

[@StarfishPrime7]

Great video. Exactly what I needed to learn.

[@RetroCarGuy530]

Great to hear!

[@ArsonistArborist]

This really clarified a few things. Thank you!

[@jacklawer6389]

Gr8 video, just subscribed. Finally i found a video that expains it, I was so confused, now I am educated. Thanks

[@enginebrakejake]

KZbin needs video's like this. To the point and very informative. Thank you! This is exactly what I needed.

[@tannhattran]

Great teacher ! May i ask you,if i need connect a pair of DRL ,so can i join 2 wires to 1 fuse tap or i have to looking for 2 ACC fuse spot to wiring them separately?Thanks for info !

[@RetroCarGuy530]

It depends on how many amps each DRL requires (peak startup amp draw and steady state amp draw). If the peak amp draw of both DRLs is below the available and supported amount of amps, you can join them together and use one fuse tap. For example, if your fuse box fuse socket can provide 10 amps (based on calculation in this an my FAQ video), the fuse tap wire gauge (usually 14 or 16 awg) can support the required 10 amps and the combined amp draw (peak amp draw of each DRL added together) is less than or equal to 10 amps, you can use one fuse tap. If amp requirement for both DRLs exceeds any of the mentioned limitations, then you would need to find a second fuse tap to power the second DRL or use the a relay to supply the power (see below). When more amps are required than a single fuse tap can provide safely, you can use a relay to supply power to the new accessory (DRLs in this case) and have the fuse box fuse tap provide the power for the control side of the relay which usually is very minimal (1 to 2 amps). The relay can source the power for the new accessory directly from the battery (with an in-line fuse size appropriately based on the new accessory's amp draw requirements for safety).

[@tannhattran]

@@RetroCarGuy530 thanks Teacher,its more complicated than what i am thinking.So for install a DRL which way you thing the easy and safe?Someone use tap fuse,wiring direct to acc fuse leg, connect to the relay(i dont know this one),or use the controller module(i dont know it will drain the battery or not) Thankyou for your advice 😄

[@RetroCarGuy530]

If you use a relay for the DRLs, the control circuit of the relay could be connected to a fuse box fuse socket which supplies accessory (switched) power. That way, the power will be turned off to the control side of the relay when the vehicle's ignition switch/system is in the "off" position so that you don't run down your car's battery. If the power draw of the DRLs is low enough to be powered directly by only using a fuse tap, the same would be true for this configuration in that you would need a fuse socket that supplies accessory (switched) power to prevent running down your car's battery. In either situation, the accessory (switched) power obtained from the fuse tap would be sent to switch in the interior of the car. That switch is how you would turn the DRLs on/off. If using a relay, the power from that interior switch would go to the relay's control side. If powering the DRLs directly from a fuse tap (without a relay), the power from the interior switch would then go to the DRLs. My personal preference would be to use a relay to control/send power to the DRLs and that way the fuse tap only needs a small amount of power to control the relay instead of needing to power the DRLs directly.

[@tannhattran]

@@RetroCarGuy530 Thankyou so much Teacher for your quick response.Im interest making my own car DRL but the relay wiring as you recommend i dont have any experience before,so do you have any quick video for instructions?Any advise will be great ! Im appreciated 😃

[@RetroCarGuy530]

In your comments, please make sure you provide at least one space between sentences, especially after a period that ends a sentence. If there is no space after the period, KZbin believes it's a link to a remote site which I've setup as not allowed on my video comments and I have to release the comment each time. Thanks. In my FAQ video on this topic kzbin.info/www/bejne/ep-9ZqqYlKZorKc , I discuss a relay solution for providing power to the new accessory (or DRLs in your situation). I don't have a video on how to install / use a relay, but a high level overview is discussed in that other video. I typically use a four pin relay for this type of circuit. Each pin of the relay has a number associated with it and they usually go as follows: Relay Control Circuit Pins: 86 = Positive trigger source. 85 = Ground. Relay Power Circuit Pins: 30 = Connected to the vehicle's battery positive terminal. This wire should have an in-line fuse to protect the device/relay. 87 = Positive power supplied to the new device (DRLs). When the power obtained from the fuse tap passes through the accessory (DRL) on/off switch when it is turned on, power is supplied to relay pin 86. The electromagnet in the relay is energized as the power flows from pin 86 to pin 85 (ground). When the electromagnet in the relay is energized, the relay's internal switch is closed to allow power to pass from pin 30 (battery power) to pin 87 (device power). The power provided to the device via pin 87 continues until the "Positive Trigger Source" power supplied to pin 86 is removed. Removing power from pin 86 "Positive Trigger Source" allows the relay's internal switch to open and the power supplied to the device (DRLs) is removed because the battery power from pin 30 can no longer pass through to pin 87 (or the device / DRLs). The control circuit of the relay (Pins 86 and 85) should require a very low amp fuse (1 or 2 amp) in the upper slot of the fuse tap. It does not require much power to energize the electromagnet in the relay, thus why you should only need a small amp fuse in the fuse tap upper fuse socket. The in-line fuse in the wire that connects to pin 30 of the relay should be as close as possible to the battery to help protect all of the wire running from the battery, to the relay and beyond to the device (DRLs). The amp rating for that fuse should be no larger than what your accessory (DRLs) require and the wire gauge supports. Please refer to your DRL's documentation to identify what the amp requirement is for the DRLs. The "Positive Trigger Power" supplied to pin 86 of the relay should be accessory (switched) power to prevent the running down of the vehicle's battery if you leave the DRL switch on when you turn off the ignition. The fuse tap should be plugged into a fuse box fuse socket that provides accessory (switched) power to the DRL on/off switch and then the DRL on/off switch power output wire should supply the power to relay pin 86 "Positive Trigger Power". Here is one of my Amazon US affiliate links that shows a relay that I've used in this manner. amzn.to/3s7jbZM This product listing includes several pictures and there is one that matches up with what I've described in this posting. "Normally OFF Relay with a Positive Trigger". I'm not stating these are sufficient for your DRL installation, but it's at least a reference point to start with including the pictures on the product listing page. Any and all modifications you make to your vehicle are at your own risk! It's extremely difficult to give electrical advice via comments on a video, so you must make sure you're comfortable with the topic and modifications you attempt on your vehicle.

[@marte1a256]

So using a multimeter do I set it to 20 V DC and insert one lead into the fuse contact and one on to ground, or do I insert both leads one into each side of the fuse contact?

[@RetroCarGuy530]

To see which side of the fuse socket provides power, you set the multimeter to 20 V DC, connect the black/ground lead to a ground point on the vehicle and then use the positive/red lead to touch the fuse box fuse socket contact(s).

[@FrankSr1st]

Hi, thanks for an informative video. I've recently purchased a new steering wheel that includes a button to heat the steering wheel. After replacing the old steering wheel with the new, I find that the left controls work, specifically for the cruse control, but the button to heat the steering wheel does not work (expected). I'd like to make the heat on the steering wheel hot. Can you tell me if by running a wire from the clock spring to the fuse box will help to make the heated function hot?

[@RetroCarGuy530]

It will take some research on your part to see what is and is not present in your vehicle to know what the correct steps are to install and power the heated steering wheel feature. It's been my experience that most heated steering wheels require 15 or 20 amps to power them. My wife's 2017 Kia Soul uses a 15 amp fuse for that circuit in the fuse box. This is where it gets a bit tricky trying to power something that requires that many amps with a fuse tap. Most fuse taps have a 16 awg or 14 awg wire coming out of the fuse tap to send power to the new accessory. A 16 awg wire can only supply 20 amps in a wire length of no longer than 2' to 3'. The issue then becomes finding a fuse socket in the fuse box that can provide the required amps without impacting the pre-existing circuit or wiring. If your vehicle has an unused fuse socket intended to power a heated steering wheel, that might be best to use (assuming the wiring isn't already present in the vehicle for that feature). Then comes the issue of how to control the on/off nature of the heated steering wheel feature. The button may be present on the steering wheel, but the feature may or may not be enabled in the vehicle's body control module (BCM). The control wiring likely runs through the clock spring, but the power for the heating element(s) may or may not. You would have to verify that with a wiring diagram for your vehicle. If you're extremely lucky, the BCM will have that feature enabled, the wiring will be present in the steering column for the control circuit (button) and the heating elements. I wish I could give more specific information to you, but this type of task involves several things (fuse box, clock spring, BCM) and I just can get to that level of detail with something like that.

[@JohnnyLawBMC]

Excellent information and product. I want to hard wire my trailer camera monitor as well as my dash cam because, who the heck still uses cigarette lighters for power except to charge our cells. Thank you for sharing

[@byaalumni6907]

What's the multi meter supposed to be set on when looking for the power in the fuse box?

[@RetroCarGuy530]

Test for 12-volts DC, I need to set my multi meter to 20 VDC testing mode. This allows the meter to test and display voltage levels for DC power up to 20.0 volts DC.

[@alexhurtado4708]

Great video! Two questions came about. 1) If i am using an existing fuse (5Amp) and placing it into the bottom AAF slot, does the upper AAF slot need to carry the same amperage fuse or can that vary? 2) Can I mix 12 awg and 16 awg between installs - my light pods come with 16 awg, but i will be extending the length with 12 awg, then connecting it to a 16 awg quick disconnect and then back to a 12 awg - the light pod is only 3.5 Amp. Thanks in advance.

[@RetroCarGuy530]

Sorry, I didn't see this question before seeing your other question I responded to. KZbin posts are hard to follow/respond to in volume. The lower fuse socket in the AAF holder is for the original fuse in the fuse box fuse socket (if one is present at all). The upper fuse socket in the AAF holder is where the fuse for the new accessory is to be placed. Never install a fuse in the upper fuse socket of the AAF that grossly exceeds what the new device/accessory requires. In the case of a 30 amp fuse for the wipers, the 30 amp fuse goes in the lower fuse socket of the AAF holder and the light pod fuse (5 amp for the 3.5 amp load) goes in the upper fuse socket of the AAF holder. If the light pod only requires 3.5 amps, the 16 awg wire should be sufficient for its power needs. You can intermix wire gauges AS LONG AS the wire gauge number is lower than (bigger wire) the wire it's being spliced together with in the circuit. Meaning, you should not use a 18 awg or 20 awg wire in that circuit since the larger awg number is a smaller wire. You should also minimize the amount of wire in the circuit. No need for a bunch of extra wire in the circuit. There are a couple of different trains of thought on this topic of using a fuse tap (AAF) to obtain power for a new device/accessory. What I demonstrate in this video is the "in parallel" approach of routing the power through the fuse tap. The power obtained from the fuse box fuse socket is directly routed to both the lower and upper fuse sockets in the fuse tap. There's another approach which would be labeled "in series" power routing approach. That's where the power from the fuse box fuse socket goes up the right leg of the fuse tap, through the lower fuse in the fuse tap and then down the left leg of the fuse tap to the original fuse box fuse socket and it also goes then up to the fuse tap's upper fuse socket. All of the power load runs through the lower fuse in the fuse tap. Which approach is best to use will result in spirited discussions/debates. The "in series" power routing method can be seen as the absolute safest approach, but it may also lead to blowing the original fuse in the lower fuse tap fuse socket since both power loads are being run through the lower fuse. For dash cameras, radar detectors and similar power demanding devices (usually 2 or 3 amps and very often dash cameras use less than 1 amp), the "in parallel" power routing approach is very safe. It will only be adding 2 to 3 or often less than 1 amp to the circuit that is supplying the power to the fuse box fuse socket. I have another video that tries to explain the "in parallel" approach a little more in depth. kzbin.info/www/bejne/j3_GYXmcmrFpqNk

[@pcrate20]

hello , good video I need some recommendations, I would like to install a hardwire kit for my dash cam , and I found 2 empty slot that I would like to use it, first: 12.2 Volts (ignition Off) and second 14.3 volts ( ignition on), my question is: what type of fuse used for each one and what type of Amp? and also I see in your video that in my case I don't have to used to fuse is correct?. Thank you.

[@RetroCarGuy530]

If you have one fuse box fuse socket that provides constant battery power and one that provides switched/accessory power that are currently unused, then yes you should be able to use those for the hardwiring kit for your dash camera. If your hardwire kit is a 3-wire (BATT+, ACC+, Ground) then you connect the BATT+ wire to the fuse tap in the fuse box fuse socket with power on all of the time. You would connect the ACC+ wire to the fuse tap with switched/accessory power and the ground wire to a good ground lug or body panel where a pre-existing screw/bolt makes contact to clean metal (no paint or clearcoat on it to allow the ground to make good contact). If your hardwire kit is a 2-wire (BATT+ and Ground) then connect the BATT+ wire to the fuse tap in the fuse box fuse socket that provides the type of power necessary for your dash camera operating mode. If you only need the dash camera to operate while the vehicle's engine is on/running, then connect the BATT+ wire to a fuse tap installed in a fuse box fuse socket that provides switched/accessory power. If you need it to run in parking mode, you would connect the BATT+ wire to a fuse tap in the fuse box fuse socket with constant battery power (on all of the time). Connect the ground in the same manner as mentioned above. Make sure the hardwiring kit has some sort of battery low voltage protection so the dash camera won't kill your car's battery. If the fuse box fuse socket did not have a fuse before the fuse tap is installed, then you only need a fuse in the upper socket of the fuse tap and the power from the fuse box fuse socket must be provided to the left leg of the fuse tap. All of the dash camera's that I've tested the power consumption of during my reviews of them consume 1 amp or less (12-volt system). You could put a 2.5, 3 or worst case a 5 amp fuse in the fuse tap's fuse socket for the dash camera. No need to get a high amp fuse for a dash camera and using a fuse with an excessively large amp rating is not good/safe for the device or the car's wiring.

[@pcrate20]

@@RetroCarGuy530 thank you very much I appreciate your help

[@tomasdabasinskas8977]

Thank you. Helped a lot. USB charger installed properly and working.

[@iftymohammadi3312]

which side of the fuse for your new accessory do you have to insert on the fuse tap. Like on the fuse tap the left side pin draws the power and power goes out on the right pin. Like do you have to insert fuse the right way like the fuse tap.

[@RetroCarGuy530]

A blade fuse does not have "direction". You can insert the fuse into the fuse socket in either way. I usually insert the fuses so the amp ratings are readable, but again it's not a requirement.

[@garyd395]

So I have a VIOFO a139 dash cam with hardwire kit and fuse tap,fuse tap already has a 3amp fuse.if I have an unused fuse slot,that would be ok to use as long as there’s power?also will I need to put another fuse in the empty fuse tap with the 3amp?

[@RetroCarGuy530]

A dash camera is a low power demand device so that’s why they’ve supplied the 3 amp fuse. If the fuse box fuse socket is unoccupied and it provides the power required, then yes you should be able to use that fuse box fuse socket. The rule is that if the fuse box fuse socket did not have a fuse in it before installing the fuse tap, the fuse tap should only have a fuse in the top fuse socket of the fuse tap leaving the lower fuse socket of the fuse tap empty.

[@garyd395]

@@RetroCarGuy530 just want to thank you so much, just hardwired my dashcam with your help. Everything is working perfectly.

[@abdullast3434]

Thanks for sharing. If the fuse in original tap is 15 amp, what a fuse should I plug in the accessory tap?

[@RetroCarGuy530]

There are several factors that go into what the proper amp rating should be for the fuse for the new accessory. First off, you need to figure out what the power demands are of the new accessory. I cannot state with any degree of certainty what the maximum power demands are of the new accessory. You need to refer to the new accessory's documentation or labels on the accessory to see what its max amperage requirements are for that device. Without this information, you cannot properly determine whether a fuse tap is the right approach and whether it's safe to use a fuse tap in a particular fuse box fuse socket. Once you know what the amperage requirements are for the new accessory, you'll need to decide if the fuse box fuse socket and the manner in which it obtains its power can sustain the pre-existing 15 amp load and the power demands of the new accessory. There are so very many thoughts on this aspect of the process. Adding a fuse tap with the left leg of the fuse tap obtaining the power from the fuse box fuse socket is known as an "in parallel" installation of the fuse tap. That being, the power from the fuse box fuse socket is being provided to both circuits directly in the fuse tap. If the manner in which the power is provided to the fuse box fuse socket is already supplying 15 amps for the original circuit, you may not have a whole lot of additional amperage left over for a new accessory. Usually adding a fuse tap for a low power demanding devices (dash camera, radar detectors, etc) will usually only need 2 or 3 amps to operate. Most 2-channel dash cameras operate at the 1 amp or 0.5 amp range. Obtaining power for lower power demanding devices is usually something that can be done using a fuse tap with something already needing 15 amps. The original fuse box fuse would go in the lower fuse tap fuse socket and the new accessory fuse would (being a 2 or 3 amp fuse) would go in the top fuse tap fuse socket. There is a different train of thought on using a fuse tap and that being making the right leg obtain the power from the fuse box fuse socket. That routes the power through the bottom fuse and then up to the top fuse for the new accessory. That's also known as the "in series" power routing approach. There are pluses and minuses to this approach as well. With all of the power running through the fuse in the lower fuse tap fuse socket it better protects the wiring that provides the power to the fuse box fuse circuit, but it also means you could be blowing the fuse in the lower fuse tap fuse socket if the load for both circuits exceeds the amp rating of that fuse (15 amps in your example). I tend not to use this approach, but others will argue this is a safer approach than supplying the power to the left leg of the fuse tap. If you have a new accessory that requires 10 to 20 amps by itself, that's when I start to suggest using a separate relay that obtains power from the battery of the vehicle (with in-line fuse) and then the power necessary to control the relay (if you need switched power) can be obtained by using a fuse tap since the control circuit for a relay is usually requires very little power (1 amp or less). As you can see from my response, this is not a topic/question that has a simple answer.