Another Lesson In Voltage Drop - Don't Skip The Basics!

Seems like we cover this all the time, but it is a very essential test for any component that you are testing. This is not just for starters and alternators. Hope this video helps you in your diagnostic thought process.
-Enjoy!
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Disclaimer:
Due to factors beyond the control of South Main Auto Repair, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. South Main Auto Repair assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. South Main Auto Repair recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of South Main Auto Repair, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained.

[@TStheDeplorable]

An old man's car died in the McDonald's drive-through. After pushing him out of the lane I figured out that it was getting no fuel. I diagnosed a dead fuel pump, and he said that was his third dead fuel pump in 18 months. But I also noticed on the computer that the car was showing only 10 volts when running. I replaced the fuel pump and his car ran again, but I also knew that the low voltage could be the reason the fuel pumps were dying. The very first thing I checked for voltage drop was from the battery post to the battery clamp, and there were my 4 volts, basically two volts per post. I removed the clamps and found both posts coated with something like varnish. I cleaned them and boom, 14 volts when the engine was running. Hopefully that will keep the new fuel pump from burning out fast like the previous ones. By the way, I'm a DIYer who learned voltage drop testing on this channel (along with most of everything else I know about cars).

[@user-fw8kt9dq9m]

that's called low voltage burnout. as the voltage decreases, current consumed increases causing premature wear. also why it is not recommended to keep cranking the starter when the battery is low. if you ever see a car keep blowing bulbs there could also be a similar issue. great job helping the old dude out!

[@dans_Learning_Curve]

Awesome!!! 👍

[@phreakyzeke5824]

Ive made thousands of dollars using simple good techniques i picked up from watching sma

[@-BuddyGuy]

​@@user-fw8kt9dq9m I think that only applies to motors or possibly solenoids but on a bulb circuit it's simple V= IR there's no back EMF or whatever

[@richarddiaz8248]

Me too I learned a lot from this guy

[@adrenna123]

Retired electrical engineer. Your explanation is spot on. Ohms law says it takes 1 volt to push 1 amp through 1 ohm. Every connection, piece of wire and anything else between two points is potential resistance. The rusty terminal caused the extra resistance in this circuit. The conservation of energy law says that energy cannot be destroyed, just transferred. With resistance, its's transferred to heat. As the temperature on that rusty terminal was raised, the resistance got worse and made the voltage drop worse until the point where there wasn't enough voltage to start the car. We saw this on the Honda battery terminal in your last video when you "let the smoke out". Again, spot on, perfectly explained and easily understood..... When your body gives out from working on cars, you should teach......🙂

[@elmaknon83]

👍

[@adambell2068]

He teaches with every video he posts!

[@61rampy65]

Fully agreed! I, too gave up mechanics to teach at a mechanic's school. Did it for 18 yrs. Let me clarify Ohm's Law: Volts= Amps X Resistance. So, 2 volts will not push 2 amps of current thru 2 ohms resistance. Electricity is so easy, once you know and fully understand how it works, but it is a total mystery if you don't understand it.

[@jpol3808]

​@@61rampy65lol Your both correct! 1 v = 1 amp x 1 ohm, and 2 v does not = 2 amps x 2 ohms. 😮😂

[@johnnyblue4799]

@@61rampy65 Electricity is easy in DC... things get a little bit more complex in AC. Luckily not an issue in the car world.

[@beefeekeefee]

Can't believe whoever went through the hassle to change that battery didn't take 2 minutes to clean visible rust/ corrosion off the clamp and cable. Also can't believe anybody else does a better job of explaining electrical diagnosis and trouble shooting than you do. Thanks and keep it up!

[@carguy1312]

A hack. There are so many out there. It’s scary.

[@Bondodon1849]

agree 100%

[@s.j.5850]

Guess who pays for a new battery that they did not even need?!!

[@ykmalachi]

Why get paid once when you can get paid twice!

[@robertsmith2956]

It was completely accessible while the headlight was off.

[@booterone1]

Eric has a better understanding of electrical diagnosis than many electricians I have worked with.

[@drgdieselfrenzy7707]

Being an electrician is about knowing code not electricity.

[@danimal2013]

This is exactly why my headlights were flickering on my 2011 Silverado. Bad negative terminal at the battery. After a round of KZbin voltage drop lessons, I narrowed it down and replaced the terminal end. Fixed the problem, and gave myself confidence that “If you can do it, I can do it.”

[@chuy1674]

I have the same issue and the same truck 😅

[@danimal2013]

@@chuy1674 The battery terminal ends on those trucks are enclosed so you can’t even see the green puss taking over the cable inside. I couldn’t see it until I cut the cable off. But I figured it out with a multimeter and SMA lessons.

[@robertsmith2956]

I had a voltage drop from battery hitting radiator and loosing the acid. Lots of soldering to repair the wire harness under the radiator. Used a lot of baking soda as well.

[@clintprice2123]

You always are methodical and use logic which is why we are all here, to see a master at his craft.

[@reason2gether]

The video makes perfect sense, but the fact that they had the battery replaced to attempt to fix this problem without cleaning the terminals is crazy! Great job once again Eric!

[@s.j.5850]

Parts cannon strikes again!

[@dgk42]

I really like this channel. 1 - you cover the essentials of being a mechanic in the rust belt. 2 - you cover what is involved in diagnosing and fixing modern cars. As you said once, it is all about the data. Thankyou Mr O and Mrs O.

[@timothyoneill3154]

I repair radiation treatment systems for a living and this is a very good refresher for anyone. You did an outstanding job on this.

[@mdorf61]

The wire whisperer strikes again!!!

[@donniev8181]

Gotta love Dodge aka Stellantis for putting the battery in such a remarkably accessible position, aye? Thanks for the educational video, Eric!

[@sockmonkey3393]

nissan does it too.

[@brucedale4465]

@@sockmonkey3393both junk brands!

[@jeffreyweinzierl1509]

I learned voltage drop when I was in trade school. That was a long time ago. (1984), Over the past 40 years I've only had a handful of times when it would have come in handy, but of course, for the most part I worked at new car dealerships. I'm semi retired now and I work on old rusty junk. These refresher courses on voltage drop will come in handy. Thank you.

[@s.j.5850]

New car dealerships typically see cars that are less than 5 years old. The built-up resistance usually follows after more years have passed. Independent shops see them all the time because they work on a range of old & new cars.

[@robpinter5431]

Wow 1984....a long time ago...me too, us old school mechanics ....Yes the video was a good refresher....

[@bobderemer5015]

Eric, you are lucky. You are constantly receiving cars where ALL the swapnostics have already been done, allowing you to focus on the real problem😁

[@tsl7881]

Ha!

[@donaldhollums3278]

It’s always fun to watch a pro at work.

[@CedroCron]

So easy but people get it so wrong... I will never understand! But I guess that is what really sets shops like yours apart. "Knowing your craft".

[@vilefly]

One the days when I am feeling old, I point the FLIR camera at it after cranking the engine, and look for the hot spots. The voltage drop check is still more accurate and cheaper, though. I bought the silly thing to test cooling systems and catalytic converters, but ended up using it for electrical faults. Hotspot in a fuse box? Boom. Found it. At least it wasn't a total waste of money.

[@Motronic944]

I think that junkyard paint on the light is telling a story. Perhaps one like that's how the body shop put it back together after it got hit in the front end.

[@kimegekjr5971]

I would like to double-like this comment ;-)

[@ChrisVargasrpht2000chris]

Saturday with Mr. O is better than Saturday cartoons. You can learn so much from this KZbin Channel.

[@robinrousseau1087]

HE IS THE BEST.

[@brucehobbs1734]

Where’s Mrs. O? Always fun to watch you cower in her presence. 😂😂

[@LesReeves]

Man you have been giving some really good advice on electrical faults in the last couple of videos THANK YOU Mr. O. for your community service really helpful to the DIYers & me (retired spanner spinner).

[@toddhoffmaster6057]

It is funny just how much I learn from every video that you put out. Keep them coming.

[@chrisburgdorf7469]

This is how i fixed my son's car. Battery kept going dead. I knew it was a draw from some where. Watch a few of your other videos on voltage drop, current draw, etc. Knowing what circuits had full time power was a big help. Found the draw. What able to isolate the components. Found the problem. Thanks you for your help and breaking it down Barney style.

[@SouthMainAuto]

Glad to help 😊

[@ws2664]

I always like your electrical and voltage drop videos, using the long screw driver to get to a hard spot, I never would have thought of that. Don't ever think we get tired of them, we don't, we always learn something.

[@JohnIsett]

A most eloquent and thorough articulation of voltage drop consequences and testing. Well done, as always, Eric. Best wishes for continued success from Florida.

[@ronaldbrosius7488]

Awsome!! 2 new videos in the same day!! Thanks!! Keep up the awesome job!!

[@hughkoontz2166]

As a 26 year veteran science teacher, that was one of the best most concise explainations of voltage drop I've seen! Great job Eric

[@herbward5240]

Eric, a great tutorial. One of the additional challenges of looking for the trouble spot is finding a way to probe a connection point and the connected conductor. Over the years my collection of DVM probes with weapon sharp edges and a variety of file sharpened back probes has filled a shoe box. Surface oxidation of a connector or exposed conductor can be an additional challenge. BTW the insulation piercing adjustable needle probes made by Pomona are wonderful. I always seal the pin holes in wire insulation with liquid electrical tape afterwards. As you aptly pointed out ,every mechanical interface in a circuit is a potential failure point . Be thankful you don’t have a boat that is used in a salt water environment. Every connection point is a potential trouble spot. It’s beginning to look like this is the reason why the electrical system in the MV Dali container ship failed at a most inappropriate time. Dude, you are a wonderful instructor . With all the electronics in cars these days , an individual with a good basic understanding of electronics and electricity will be a superior automotive diagnostic tech.

[@danlemke6407]

You speak pretty good jibber jabber! I understood it perfectly. Thanks Mr O.

[@smc9764]

I learned the hard way too that checking every connection point also applies when checking for opens/shorts. I couldn't figure out why one of my TPS on the throttle body was showing 0v but everywhere in the circuit was 5v. Then by accident I pressed really hard on the connecter and the voltage came back, some how there was a failure from the back of the wire in the connector to the front of the pin, lol. I checked the voltage everywhere except the place it mattered, lol.

[@PhillipBailey]

Great demonstration! I typically teach a maximum of 0.1v per connection and 0.1v for every meter of battery cable. Never to exceed 0.5v for the entire insulated circuit or entire ground circuit..This only applies to high current circuits such as starter and alternator testing. I'll bet on that car if you cranked it for 15 seconds in clear flood mode you would be able to "see" a hot connection with a thermal camera. 1volt times 100amps is 100watts. That's got to warm up something...

[@SouthMainAuto]

Smoke is always a good visual que ;-)

[@NoName-zn1sb]

@@SouthMainAuto visual cue

[@major__kong]

In aviation, a 0.5V drop applies to any circuit carrying power not just the big ones. The tables in AC 43.13-1b go down to at least 22AWG. They also differentiate between continuous and intermittent loads. They allow a 1V drop for intermittent loads.

[@PhillipBailey]

@@major__kong that's interesting

[@throttlebottle5906]

disable fuel/spark and crank until something emits smoke.... 🤪 even if manually via starter relay jumping. wait I would never do such a thing and have never( yeah right, look for smoke first, then troubleshoot second)

[@samcooke2742]

Voltage Drop - a classic reggae song - voltage gonna drop on you...

[@JohnnyTalia]

You make the testing process so simple, but I find myself disturbed by the fact that the "other shop" was unable/unwilling/not smart enough to do such a simple test. Instead they fired off the parts cannon for hundreds of (perhaps unnecessary) dollars. Then they send the car to you, you identify the issue, and they finally fix the actual problem and the customer ends up being oblivious to the fact that they've been ripped off due to that shop's incompetence/laziness/greed.

[@peterlee2622]

Eric, you are so right when you say that everything imposes a bit of voltage drop. One item that has to do this is the fuse. It relies on having a certain resistance so that when the current gets abnormally large the wire in the fuse will heat up and eventually melt. You often see a largish fuse (e.g. 15A) protecting a circuit taking (normally) only a few tens of milliamps. The fuse size is chosen to protect the wiring and also ensure that normal voltage drop across it is small so as not to affect operation.

[@s.j.5850]

I learned that lesson from one of Eric's videos.

[@RenegadesGarage]

South Main Auto... Very well explained Eric. As always my friend.

[@REDMAN298]

Great refresher course. People always want the "fast fix" and need to realize the importance of voltage drop testing.

[@truthsmiles]

The irony is this IS the “fast fix” - this car has been giving problems for days if not weeks and Eric found the problem inside of an hour.

[@u2mister17]

@@truthsmiles You really touched on 'it' there. Remember the door flying off the Boeing 737? The plane was taken off their 'over water' flight routes because of continued cabin pressure warnings. The aircraft was talking but no one was listening.

[@bestjobdaddy6736]

Thank you for all the knowledge my friend. You have a simple yet informative way of explaining that makes it easy to understand.

[@derdan20]

Great basic troubleshooting techniques. So many take their best guess and fire the parts cannon.

[@wojciechuczyk6566]

To jest to za co szanuję Ciebie. Pokazujesz cały proces myślowy logicznie tłumaczysz co i jak bez zbędnego pitolenia. Pozdrawiam

[@DavidKing-vb9ux]

I hope some HVAC techs watch this! Over and over and over again I ask will your multimeter read minimum volts and stay locked on that reading until cleared. In 30 years I have had two that said yes. The complaints are compressor failures, compressor hard to start lights dimming when compressor starts. My favorite is we sold the customer a completely new system and it has the same issue. We are dealing with 240 VAC at maybe 100 amps starting current. They get a good meter and find that 240 VAC is dropping to 150 VAC bingo Yahtzee! Now it’s always I will have customer call an electrician. Why just do voltage drop tests all the way to the distribution panel buss bars. If it’s dropping at the buss bars it’s a power company issue. So let’s save the customer the electrician cost and direct customer in the correct directions. Multi meters without low voltage lock are like an amp probe without a display. Thank you Eric for showing the value of knowing and not guessing.

[@arlynsmith9196]

A Master class! I am thankful you do not charge what your classes are worth! Thank you so much!

[@GunfighterWyo]

Nothing like a professional who knows what he is doing. Based on the equipment Eric uses, I spent the money on a used meter like his. It has kept me out of trouble several times. Thanks for the great video.

[@amber07701]

Very informational video like most that you put on "the KZbins". Keep up the great work

[@myZcarlife]

So I put this video to use today. I was driving my 2007 Mazda 6 Wagon. I have a power adapter in the 12 volt outlet that also displays voltage. It was showing low as usual. When I got home, I checked the battery voltage from positive to negative, and it was 13.7V. I checked from positive to the shock tower, and it was 13.2V. Then I checked from the middle of the negative post to the shock tower, and there was my missing 0.5V. Thank you for the reminder, Eric.

[@jimandnena4]

I started learning electronics in the 50's by going on service calls with my dad to fix people's TVs. Yes, TVs were once repairable in the home, usually by replacing a vacuum tube or 2. There were no circuit boards; all the connections were point to point wiring. Any bad soldering joint could cause problems. When I started repairing electronics, I learned that most of the "unsolvable" problems were caused by bad ground connections. The higher the circuit current was, the bigger the voltage drop.

[@jdjd0711]

Several years ago my wife bought a Chrysler Pacifica at another state car lot. (When Pacifica was an Suv type vehicle). It was low mileage great condition, optioned out and a great price. We picked it up on vacation on the way home. About 150 miles on the 250 miles trip the dash went dead and engine turned off. A call to the dealer who denied any knowledge advised to take it to a dealership. It was late afternoon Saturday so nothing open. I made it the rest of the way with no more issues. Now thinking I'd been scammed (deal too good to be true). I simply Googled the model and symptom and then answer was a bad connector on the hot cable from the battery connector to the fuse module. Monday I called the local deal to get a replacement. Of course back ordered with no known date. I measured the diameter and length of the cable, went to tsc and picked up a riding lawnmower starter cable that was the same diameter but 1 inch longer. I swapped the cables and she drove it for the next year and we sold it. We made a little over $4000 on that vehicle by replacing a $3.95 cable.

[@NoName-zn1sb]

Yea TSC!

[@mikechiodetti4482]

Aftermarket systems installed on vehicles can cause a LOT of voltage drop problems in fleet vehicles. Then they became our problems when they didn't work right. Or when a three axle tractor with trailer had a problem with the OEM instrumentation not reading correctly and for several months the problem was chased. When the vehicle came in one day the dash voltmeter read in the 11 volt range. With the engine running, one of the two group 31S batteries read 14.2 volts the other read 12.4. Both batteries had individual positive and negative cables going to the starter. When the cables were checked by pulling on the cables near the lugs (terminal) at the starter one cable pulled out of its lug. It took a little work to fix it but once repaired both batteries read 13.5 volts, no more voltage drop and that repair eliminated all the electrical problems in the vehicle's instrumentation. YA. VOLTAGE DROPS ! ! Good one Mr. O!

[@cullenmiller8170]

Just watched Paul’s video and then yours popped up. Have a great Saturday.

[@kenmohler4081]

A very good lesson. Thanks, Eric.

[@user-cf5rx2kp7v]

I’m no electrical guy but I understood this video. The paper and marker made it easier to understand. Thanks Mr. Eric ! Keep up the good work ! 😁

[@dav1dsm1th]

That could be the first time I've ever seen Luna's cry for attention get ignored. I'm sure she got extra ear scratches after the camera was turned off. Thanks for the videos, Mr O.

[@bostedtap8399]

Every day is school day. Excellent diagnosis and explanation Dr O. Thanks for sharing

[@user-iv2tu4wq7t]

Mr O, you are a FANTASTIC Teacher!!! I wish I knew how to do voltage drop testing when I was working as a mechanic It would have come in VERY handy!!! And you explain it clearly and concisely and in a way that’s easy to understand!! Thank you for sharing your expertise with us!!

[@ablelock]

Great video keep up the good work Eric all of us DIYers all appreciate that information that we learn from you. 😊

[@russjam121]

Thanks for a good explanation 😊

[@SouthMainAuto]

Glad it was helpful!

[@rawcado]

@@SouthMainAuto Nah, wasn't any help because I don't have any of those problems because I learned years ago that those aftermarket replacement battery post and cable clamps are crap and nothing but trouble, and they probably shouldn't even make them so people would have to buy and install a new cable, which is what the real solution is. Any time you see those replacement clamps you can bet you're gonna end up buying a new OEM type cable and you'd be better off doing that first instead of last.

[@ThunderbirdRocket]

That makes sense AND makes cents 💰 in saving us money with your techniques ! Thanks Eric . 👊🏼 🔥 💻 📈 💡

[@marklessard4499]

Eric, I just fixed and issue on my boat, by knowing how to check for voltage drop from watching your other videos, this one is great for learning, keep it up.

[@edogle8163]

Thxs Eric some good info....You showed us in lasted video the cable exchange....Thxs again...

[@2-old-Forthischet]

In prior years, my parts cannon solved the problem, eventually. Thanks for the video.

[@michaelskinner896]

Excellent walk-thru and very useful. Thanks for this!

[@jeffcooper5789]

I saw your portable cat scan machine walk by. Informative video and thanks for the instruction.

[@hansjansen7047]

This and the two Honda videos are invaluable ( by which I mean there is no way to give it a greater value)

[@marcokahny709]

Thanks for the education Eric I became a pretty damn good troubleshooter from watching you from the early days before dollar store glasses for both of us. Your explanations of electrical troubleshooting wasen't lost on me Thanks from an OG

[@user-ps8ij4oj2d]

I worked in electronics for many years do bench repair of PC boards and used this troubleshooting method all the time. Worked with many techs that would shotgun and sometimes finally got a fix.

[@bobby9195]

Thank you for the educational video Mr Eric. I appreciate your time and trouble to bring us this

[@LouJustlou]

Glad to see the analog laptop and a brief "cat scan" by Luna. Haven't had a chance to apply this lesson yet, but I'll be ready when I do!

[@wadepatton2433]

12:02 Kitty sighting. Appears to have been underneath the car checking connections for rodents. Or asleep.

[@glassvial]

Luna was doing a cat scan.

[@wadepatton2433]

@@glassvial and kitty head shake--that must be the "negative" sign for scan results.

[@spencerduncan]

Thank you Eric for dumbing the process to the basics. ❤

[@billmurphy9921]

Great explanation. Thanks for posting. Some kids these days could learn a lot from you!

[@kimegekjr5971]

Underrated video. Thank you for reminding me. I would never use a connection that rusty though. Keep it clean.

[@Hooch737]

I learn something new EVERY time. Thank you!

[@garysgarage3669]

My opinion is that you are the best teacher on the World Wide Web.

[@troytheconsumeroflargequan3254]

Master class in trouble shooting voltage drop. Thank you Professor O.

[@George-ox6ix]

Oh brother... I just bought a 1988 dodge d150 2wd pickup with an electrical problem that I didn't realize. The left turn signal didn't flash and the left brake/parking lights are dim. I changed the bulb 1157. Of course it still doesn't work. Also, when in reverse and applying the brakes the backup light goes out, left side only. So... a short! I followed the wires from the back light along the frame to the engine compartment into a bundle of wires. I did check wiring diagrams but I'm not sharp enough. I bought a Power Probe PPECT3000 short/open circuit finder that plugs into the brake light socket, nice, followed the wires with the probe beeping along into the engine compartment to the fire wall behind the air cleaner. Removed the air cleaner, opened the wiring harness best I could, removed old electrical tape and exposed a clump of solder with a pigtail to ground. It's 2 wires that were cut then twisted together with the pigtail and beautifully soldered. I mean a sweet solder job. Anyway, It's not a factory connection but it has been this way for years due to the age of the tape. Even with this fancy tool it doesn't narrow down the exact wire with the power signal so I'm not sure this solder clump is the same wire or wires from the back light. I think I should cut out the soldered wires reconnect them color to color and see what happens... ideas?

[@abefroman1986]

You should do a whole series (over time) starting with a video like this of basics. And create a whole playlist about it. You have so many videos over the years and I know you have covered it all but having it in a playlist would make it easier for new people to find it. So many of your stuff has great information but it gets lost in the tons and tons of diag videos you have. Love the channel been watching since 2015 keep it going. Also make more cooking videos on your other channel we love it too!😊

[@AnthonySmith-hr2kp]

Thanks for the....explain. Learned much, as I always do the way you explain things. Thank You Mr O. So simple!!!

[@Embermist69]

Didn’t know you had a catwalk in the shop Eric. Saw Luna there strutting there like a queen she thinks she is. 🤣

[@Jimmyky77]

You are a master at his craft Mr O 🧐

[@erics9213]

Thanks, I learned something today. I was going to ask about measuring OHMs but you answered my question.

[@wolfparty4234]

Perfect!! 👍🏼 It’s crazy how that connection is robbing 1 Volt just bc it’s cruddy.🤯

[@MeltiahNye]

Again, I like your analogy of voltage as being a pressure difference...

[@SiempreAdelante559]

Thank you for this informative video, my 98 c5 died and this explained where to find my drop. New battery and different headlights no more voltage drop

[@fredflintstone8048]

Disconnecting and cleaning all ground connections would be the thing to do if we don't know how to troubleshoot using voltage drops. Having the scope is perfect because we capture the voltage level when doing something like turning the ignition switch etc. Much nicer than using a VOM. The next best thing would be using a VOM that records min and max voltage levels.

[@joeyabb1965]

I’d love if we could test people for voltage drop. 😂

[@kiwiingenuity1677]

Like Trump.

[@alabamared2568]

​@@kiwiingenuity1677he may have a voltage drop but his battery isn't completely dry like Mr where am I!!!

[@frankdaiii6403]

I always use a garden hose analogy when I explain voltage drop. There's a hose with a "gun" attachment on the end and the spigot is on. Kink the hose (high resistance) and both sides of the kink will still hold pressure (potential difference measured with no current). Spray from the gun to create flow (current). There's only a trickle out of the gun, but the other side of the kink is still hard with pressure. release the trigger and eventually both sides will equalize (measuring without current.) Great video as always!!!

[@scowell]

The key is *current*... V = IR... volts equals amps times resistance. I.E. if you don't put a load you won't see a drop. Eric mentioned that at the end.

[@robpinter5431]

Great explanation Eric, as a retired mechanic of over 40 years both civilian and military, these skills of basic diagnosis are being lost by plug in the computer for the code. In the Australian Army the vehicle technicians are also taught auto electrics as a combined trade, I was posted to the apprentice school as an instructor teaching auto electrics, I had to simulate faults so that the apprentices could diagnose problems, unfortunately with new vehicles faults don't occur as often as older vehicles. Thus it is difficult to get the required experience, Your video's are great.

[@alantorrance6153]

Thank you for the refresher or ab initio training course. Much appreciated.

[@user-lq6yo8tp5g]

Thank you for taking your time to explain the causes and reasons for all of your repairs......I either learn something new, a better or new way to do the repair or diagnosis, or am reinforced in my process......You are an asset to you tube and entertaining to boot!

[@pepawspostings9231]

You explain things very well and I have learned a great deal by watching your videos. Keep em coming!

[@wadepatton2433]

I got it the first time, but hey--this is good stuff and bears repeating. It's going to be instrumental in getting my old rusty diesel truck back on the road, or at least in farm service. Thanks for showing how practical and necessary and simple it is.

[@devttyUSB0]

Thanks Eric. Your explanations are so clear, if a viewer doesnt understand voltage drop after this, they should perhaps reconsider their interrests.:D

[@4b131]

Great Saturday morning coffee video, love all the electrical vids Eric. Have a great weekend 👍

[@davidgreen4888]

Didn't quite understand voltage loss before. I think I have enough now to be more effective. Thanks for the course.😊

[@steveschaff8848]

Thank you for the refresher

[@OcRefrig]

Great video ! Another tip people - Never ever Bolt something electrical to a rusty surface bolt etc. When dealing with Electrical All Connections Must be Bare Metal Shiny Clean & Tight.

[@civicdxrunner]

This is my weakest point still so far. I work for a Honda dealer in Missouri so it's not used a whole lot but will share this video and find scanner danners video and show them because there will be a time when we need it. But as a nervous diagnosis tech I do have to say that Eric has really helped me through all my learning. Manufactures test only do so much but to see it in real time really helped me out and all the master techs look at me weird with my testing ways.

[@daverichards190]

Using voltage drop troubleshooting I was able to identify a mostly burned up alternator B+ cable that was affecting charging, it had destroyed 4 alternators that had been replaced by other shops. 2010 Odyssey. I also use a load-pro lead set on my Fluke. Thank you for always reminding us of the basics.

[@latinman9791]

When you have a problem like this and you got an old car the best thing to do is just go ahead and change the positive and the negative cables that will eliminate your issues and your your battery will hold the charge and it's a cheap fix especially if you do it yourself

[@peglegtoo]

This saved me replacing a starter and battery on my boat which it really seemed like both were bad... by testing and not guessing it was obvious I was getting voltage drop on a corroded positive battery cable. the negative side was fine.

[@davidfoulk3078]

You said “Take my word for it” why would anyone have to take your word for it?? You’re always dead on right!