Hummer H3 and 3.5l: How to uninstall and reinstall the fuse box

In this video, I explain how to properly remove and reinstall your H3's fuse box.
You need to be careful to not bend any pins or damage the wires if you decide to do this!
Feel free to visit the Pro Bono Shop at pro-bono-mechanic-shop.creato...

[@probonomechanic]

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[@trevorgildersleeve3914]

Thank you. Saved me! I linked this video to a hummer forum thread where for YEARS people have been incorrectly following the advice to FORCE these connectors together. The original photos from 2011 show the connectors in the lowered position with the hooks folded. So.. everyone is just crushing those hooks. Including me. Then things weren't working, just like many of the comments in the old thread.

[@probonomechanic]

I just realised it was a problem when I got comments on my video on how to change the alternator. So people said their hummer were having weird problems and they couldn't figure why. That was the only thing that could have been the problem. Happy if it can help, honestly!

[@trevorgildersleeve3914]

Yes, this video saved me and I'm sure will save countless others over time. Much appreciated!

[@Hekomanspace]

@Pro Bono Mechanics That's The Business! Thank You. I Took My Fuse Box Out To Clean And Dress My Engine Bay, And When I Started Putting Things Back Together, Guess What? The Hummer Wouldn't Start... Went To KZbin, Seen Your Video, Thought To Myself, Uhmm? I Didn't Do Anything With Fuse Box Like You Instructed... So I Went Back And Uninstalled Fused Box, Followed Every Step In This Video, And Hot Damn! Wouldn't You Know It, She Fired Right The Hell On Up... Happier Than A Punk In A Winnie Factory Thanks To You, I Learned The Correct Way To Install My H3 Fuse Box. You're The Man Bro! Thank You, From A New Subscriber...

[@probonomechanic]

By Napoleon's booster seat! I'm glad to hear it! Happy it work! What were you working on to dress the whole thing?

[@Hekomanspace]

@@probonomechanic We Took Stuff Apart To Detail The Engine Bay, And We're About To Dress All The Wiring, Then We're Painting Everything Plastic In A Glossy Black... But Everything Seems To Be So Complex And Compact When It Comes To The H3. A Real Pain In The Ass No Matter How Minute It Is Bro...

[@adamcnow]

YES, the problem is when reinstalling the fusebox make sure those U, C white hooks on the side are sticking up! (CRUCIAL STEP!) Mine were down, somehow? I figured out I could take the bottom piece off. If you're in this situation or cant' push the wires to get them up. There are 2 tabs on each side. (I used a very small flathead screwdriver to gently move the tabs to remove the bottom. Once the bottom is off you easily push it up and hear it click in place and the C hooks are sticking up properly and now you can place the top fuse part easily and hear it click on both sides. Man, i got lucky I didn't bend metal pins or break the damn thing! Thanks for the heads up!!! JK! Yours is the best video for Removing H3 Alternator on KZbin and you don't have to bend AC lines (screw that I don't need a break or leak with w/my AC!) No problem removing and reinstalling new alternator. Thank you, Sir!

[@probonomechanic]

I have to combine this video with my old video on how to remove the alternator. I think it would help a lot too. Thanks for the comment!

[@miguelperalta1946]

This helped me at my shop man, I thought I ruined someone's hummer

[@probonomechanic]

Anytime! I'm glad it helped!

[@waynehutchinson1423]

Thanks ,this helped a lot.l have never seen the under side of a fuse box,being a DIY,,but you took the time to show the pros +cons of getting at the alternator.Good job!!

[@probonomechanic]

Hi, sorry for the delay! I hope it helps, its really not fun having to do a job that you don't feel comfortable and then the car doesn't start or you have to tow the car to a garage.... I try to be as precise as possible, but we are human haha and mistakes will happen. Honestly, thanks for your comment. This help to understand if him going in the right direction with this channel! Cheers!

[@Lionheart054455]

@@probonomechanic Thank you for this clarification too👍 I have Hummer Alpha and won't start just sound click i replaceed starter and battery but still won't start 😓 i will do this to clean all fuses so 🙃

[@probonomechanic]

@@Lionheart054455 Hi, before going there and remove everything, I suggest taking a closer look at your terminals on the battery. I know some people had problems with them, and it was litterally just the terminal at the end of the cables that connects to the battery! Its a more simple check

[@Lionheart054455]

Hi 👋 I cleaned the terminals before doing anything but unfortunately it doesn't work 😕

[@probonomechanic]

Ok, so you changed the starter and battery. Both new? And since then (or before you changed anything) the H3 wasn't starting. You could hear a clicking noise? But nothing was happening. Did you see if the radio and dashboard lights where lighting up? Because right now 2 things comes to my mind with your symptoms. 1) the terminals on your battery are loose. But not on the battery! They could be loose on their cables. Makes sure the screws that tighten the terminals on the cables are tight. A lot of hummer H3 owner will swap them for newer models to prevent that situation. 2) The second point could be your antitheft that has kicked in or is causing a problem. So try the two following things and each must be done with a minimum of 10 minutes between them. Step 1: wait 10 minutes without trying to start the Hummer. Then turn your switch on the ON position and wait about 10 second or more. Then turn the key to start. If it start there is a problem with the ignition switch but you can still drive it around no problem as long as you always wait 10 second or more before turning the key from the ON position to the start position. If it doesn't work. Do you have a keyfob with the hummer? If so make sure the battery in it is good. From there sit in the car close your doors make sure the doors are lock and the windows are up. Without the key in the ignition wait about 10 minutes. Then unlock your doors with the keyfob and then put your key in the ignition and try to start it. Let me know from there

[@teriboye3544]

Your attention to detail is amazing, thank you!

[@HummerH-mo4cs]

Hey good to see a H3 Doctor helping out us H3 owners... Thank You ---Peace ! ! ! :)

[@probonomechanic]

Hahaha thanks!

[@nathangardner9395]

@ Pro Bono Mechanic Thank you so much for sharing this video. I followed your alternator video to replace the alternator and ran into the same problem... absolutely no power and the key stuck in the ignition. 20 minutes after watching this one and I was good to go. I didn't realize that you kind have to reset the terminals under the fuse block so everything lines up perfect. Luckily I didn't bend any of them over. 👍🏽

[@probonomechanic]

Happy it help! I have a few questions if you don't mind. I usually ask questions so if someone scrolls the comments they can get a feel on what to expect. Is there anything that gave you trouble when doing the job? Did you clip the connectors at the bottom of the box before placing the top part of the fuse box or did you just plug the connectors straight into the top of the fuse box then slide it into place? Was there a big difference when you pushed back the top of the fuse box in the bottom connectors with the pins in proper position? Cheers

[@nathangardner9395]

@@probonomechanic Of course. After I "reset" the connectors under the fuse block, I clipped them back into the bottom tray. When I lowered the fuse block straight down there was very little resistance and I could hear all of the locking tabs engage. Once I finally reconnected the battery, I could hear a relay in the fuse block clicking... I knew I was good then. Hopped in the truck, and I had power. The key turned in the ignition as it should, and it fired right up. Turned off the H3 and the key was released from the ignition. After watching your video, the fuse block fix was fairly easy. Swapping out the alternator was more difficult just because of how the GM engineers cram everything in there with little thought about maintenance. It doesn't help any if you have average size to large hands. Good work my friend. 👍🏽

[@probonomechanic]

@@nathangardner9395 thanks for the reply! Ya, I still don't understand why they don't put the alternators a bit higher on the engine. I know it most be for somekind of safety, but when you look at a good old V8 with the alternator staring at you with only two bolts holding it, it feels like the engineers wanted to make sure the majority of people would give up. Anyways, thanks again for answering my questions!

[@devaultc]

Man, I wish I would have seen this earlier this week! Just had a fuse that went out, one of the bigger ones, and $200 later, it’s fixed.

[@probonomechanic]

Hi Chris, sorry to hear that. What happenned for the relay to blow up? Did you guys figure it out.

[@devaultc]

@@probonomechanic yes. Had a local chain put in a battery for me. Turns out must have hooked it up wrong and blew a fuse. Will not do that ever again! Friend owns a dealership so he towed it in, two hours of looking, finally found the problem. I guess everybody assumes people know positive from negative? All good now. I wasn’t even think fuse.

[@probonomechanic]

Ouch harsh lesson! Happy it's fixed tho What year is your H3?

[@devaultc]

@@probonomechanic 2009! Bought new. 164,000 miles.

[@probonomechanic]

Nice! It's worth taking care of it!

[@RicardoGonzalez-yz1vp]

I want to thank you for this video, i was checking relays and i accidentally pulled the entire fuse box out of its holder, i pushed it back down, shut hood and the truck would not start, went back to fuse box and checked everything and all was good,still no start, so i went to u-tube and watched this video and found out why and where i screwed up at, i removed fuse box and found i had crushed the white holders to the bottom of fuse box,so i removed them and reinstalled them with two tie wraps to hold them togather, put back togather, and it fired right up, saved a wrecker and a delalership fee for fixing it..... Thanks again.....R.S.G.

[@probonomechanic]

This! This is why I'm happy to make those video! Thanks for letting me know, it helps to know it actually helps. I'm glad it worked out for you, It can be really stressful when it happens.

[@RicardoGonzalez-yz1vp]

@@probonomechanic thank you again, this happened when i had the windows down and no power to put windows up, naturally my wife was fuming because of the leather seats and it was supposed to rain,so I taped the windows with plastic bags and painters tape till morning, watching your video was a life saver, I couldn’t understand why it wouldn’t lock in till I looked at what you did, so anyway i used tie wraps to hold them in, the plastic clips were broken off and thats the only way I could think of securing the wiring to the fuse box, and reassembled before the rain started….all good 👍

[@probonomechanic]

I know the feeling of getting external pressures to get the job done hahaha. Glad it all turn out ok Did the white leg broke on the white connectors?

[@RicardoGonzalez-yz1vp]

@@probonomechanic yes the white connector clips broke off on both sides, I removed them and the casing, pushed the wire block assby, up and out 2 tie wraps around fuse blocks to keep the wire connector in place, I figured if i hit a speed bump or a pot hole and the wireblock fell out, the truck would shut off no matter where i was….👍

[@probonomechanic]

@@RicardoGonzalez-yz1vp ouchh, ya I see. Worst case scenario, if the H3 starts doing weird electrical problems, you could try to salvage some connectors from a scrapyard.

[@espineir]

Very useful and detailed video, thanks for sharing it !!!!

[@probonomechanic]

Glad it helped! Thanks for letting me know, I appreciate that!

[@finnsorteberg3258]

Great job detailing the process with close-up videoing and explanation! I’ve recently acquired a 2008 Hummer H3 Alpha that the previous owner had let sit parked for many months. I’ve got a few quirky weird and somewhat unexplainable electrical issues. The one that is most annoying involves the rear drivers side tail/brake light staying on constantly - EVEN WITH THE KEY OUT OF THE IGNITION AND VEHICLE LOCKED! Coupled with this issue is the left rear turn signal and brake light do not function at all and neither does the top center mounted third brake light. Upon checking my fuses, I discovered that when I pulled the fuse #20 (rear turn signal, hazard signal) the light went off, but still didn’t activate the brake, turn or third brake light. I’m planning to use your video guide to take out the fuse box to give it a complete and thorough cleaning with CRC electrical cleaner, check/replace all the fuses and clean all of my electrical connections that I can get to. If you or anyone has experienced these issues, please reply or pm me with how you fixed your similar problems with your Hummer I Thanks so much.

[@probonomechanic]

Hi, thanks for the comment. It can be so many things, and it's always hard to give advice without seeing the vehicle. I can try to give a few thing that I would check. You said it got park for a while....is there a sunroof/moonroof on it? If so the H3 have problems with the moonroof/sunroof drains clogging and getting water inside the body panels (upholstery), to the point of destroying your electrical components behind the dash. But it is a good call to double check that fuse box. That brake light could be grounding with an open wire or something (so logicly if you activate your signal light it won't blink, right?). Do you have a volt meter to check how much juice is going in it? Let me know your progress! P.S: check your floor on driver and passenger side for any sign of water or water damage.

[@thiagolemao]

Where are the intake sensor wires connected? I bought a Hummer this week and the sensor is there, but the connector with the wires are gone. The old owner must have disappeared with him, I don't know. I would like to know the path of the sensor wire input to its final destination. Thank you

[@dancing_on_glass46]

Hi. If really appreciate your videos and your help. I have a 2007 H3 and my transmission began to stay in 3rd gear. I found out it's in limp mode? And fuse 34 blows instantly. I think it's short to ground on the right pin if your looking from the battery twords the front of the vehicle. I have a tone on the left pin and nothing on the right side pin. I was going to pull the fuse box and try to trace the wire from there. Have you had this issue?

[@probonomechanic]

This one will be tricky. I know the battery terminals can cause a lot of electric problems. If they are still the original terminals I would change them, just a precaution. Do you have any codes that shows up when it happens? Anything happenned not too long before it started doing that? Oil change, filter change, etc. Let me know!

[@dancing_on_glass46]

No sir. I did get new terminals and a battery about a year ago.

[@probonomechanic]

@@dancing_on_glass46 ok, from this lets check 2 things. Let's check the TCM and the transmission. Follow the wire for the fuse 34 coming from the transmission and check the wires leaving the TCM and look for any kinks, small holes or rip in the wires. Sometime it can be mash between body parts or it may have been expose by a rock. I'll check of I can find the diagram for the wires in link with fuse 34.

[@OWN12S]

My 07 H3 reverse lights work, but the reverse wire near the shifter has no power when its put in reverse. You think this is a fuse problem?

[@probonomechanic]

It could be a burnt fuse, but I'm a bit confuse with your description, so I have a few questions. You said that the reverse light works, do you mean that the light bulb are good but they don't light up? You said that the wire near the switch at the shifter doesn't have power, did you test with the key in the ignition? 2 things comes to mind. 1st: check the fuse in the fuse box under the hood for the back up light fuse, and test to see if you get power. 2nd: do you have a sunroof/moonroof on your H3? If so check the front passenger side floor to see if water gets in. The module (bcm) for the lights is located on the A pillar behind a trim panel near the floor. If the drain of your sunroof/moonroof is glogged the overflow of water will run down the pillar and get in the module. (Remove the trim panel on the A pillard at the front passenger side and check your module for water or shorts in the wires.) Let me know from there! Cheers

[@OWN12S]

@@probonomechanic Yes. The reverse lights come normally. Its the reverse wire near the shifter that no longer has power. Thanks for the suggestions. I'll give them a try.

[@teriboye3544]

Where is the Discrete Logic ignition Switch fuse located!

[@probonomechanic]

I'm sorry I don't understand, the descrete logic?

[@donbass7996]

Wonderful

[@probonomechanic]

Glad if it actually help!

[@donbass7996]

@@probonomechanic I bought a Hummer H3. now I'm waiting for it to be delivered to me by trailer from Georgia. in the meantime, I am developing a knowledge base for this car. thank you very much for your videos

[@donbass7996]

@@probonomechanic and by the way, hello to you from Russia!)))

[@probonomechanic]

@@donbass7996 добро пожаловать! My russian isn't too good, but you are welcome to the channel! Don't hesitate to ask questions, and congrats on the new buy! What year and engine?

[@donbass7996]

@@probonomechanic and of 2006 3.7 liter. Original mileage 96000

[@davidbooher289]

Which fuse is LH turn

[@probonomechanic]

Are you talking about the front or rear? Check this wonderfull video: kzbin.info/www/bejne/bKqslWZ9Yrppfrs

[@michaeljanuary9744]

How do you know if you have bad connections with the fuse box

[@probonomechanic]

Hi Michael, There is really random thing that can happen when you have a bad connection. It could be from no power to certain systems, to random lights in the dashboard (like a christmas tree), or just complet absence of power to the whole system. If you didn't play with the fusebox before it happened, and that you have a sunroof, I would check the drain pipes for the sunroof. This is a comon problem and the verification is to make sure its not water leaking in your H3 and going in your connection.

[@michaeljanuary9744]

@@probonomechanic I went to the hummer turned the key then I got power to everything but would not turn over. Also I can can drive it for awhile and stop to put gas and it will do the same thing. Usually have to wait about 30 minutes and then it will start.

[@probonomechanic]

Sound like a passlock problem, and not the fuse box! It may sound really simple, but put the key in the ignition, turn it to on position for about 10 seconds then turn you to start. That 30min is the time THAT RESET EVERYTIME YOU TRY TO START IT BEFORE THE 10MIN RESET KICK OFF, you need to wait for a the anti-theif safety to kick off and let you try to start again. (So waiting a few second on the on position may let the car register the key before trying to start it.) Here is a perfect video to explain: kzbin.info/www/bejne/Y2KQqWqtfdZgjpI Just beware that trick won't work if you already try to start it within the 10 min reset time. So if you just tried it wait a 20-30 min to be safe and then try the trick. And redo the 10 second wait rules and you should be fine!

[@michaeljanuary9744]

@@probonomechanic also let say I have been driving for like 39 minutes and I’m coming off the highway the hummer will slow down by itself and reduce speed it goes to about 39 and it says reduced speed and does not matter how much I’m trying to accelerate. Also will turn off

[@probonomechanic]

@@michaeljanuary9744 Ohh! That changes a lot of thing. From here we need the year and model of your H3. Do you have a OBD2 scanner? Because the codes will limit some possibilities! Because this one message that can come from many problems. It can come from a gas pedal assembly since it as a sensor that can go out; a corroded wire to the control module for the fuel pump; a bad signal to the throttle body; and so on. Without reading the codes it will hard to diagnose.