BATTERY DEAD...AGAIN...fml

[H3Novice]

Okay, my g/f's H3 battery died. I jumped the vehicle and drove it around for about 20 min to make sure it wasn't the altinator. I turned the vehicle off. Wouldn't start...okay so it's just a bad battery.

I pick up a new battery and install it. Car starts...great my job is done...NAUGHT...Now the Stereo is malfunctioning...doing dianostics and eating CDs...I think nothing of it.

Next day the battery is dead. I blame it on the CD player that doesn't turn off when the vehicle is switched off. I pull the fuse on the CD player, jump the H3. Drive it for 20 min...turn it off...turn it back on! YES I'm done...she needs a new stereo (factory stereo FYI). I'm done...NAUGHT!

A week goes by with no problems...then TODAY she gets in the H3, won't start. Battery dead...WHAT IS GOING ON!?

[DRTYFN]

Find someone(Hummer dealer or car stereo installer) to find the electrical draw.

[3Hummer]

if its still under warranty DONT TOUCH IT ANYMORE! if you try to fix it then take it to them, they may say it was your fault it broke and not fix under warranty. Best thing would be to take it your nearest Hummer, or GM dealer to get it taken care of.

[wpage]

If you are out of warrentee. Put in a good battery. The stock ones are under powered for the H3...
Pull off the plastic casing completely, the tray under will support much more powerful/larger batteries. You will need to mod the retaining strap slightly to accommodate RV or certain Marine batteries. However they will fit.

[Ed G.]

For the first 2 months I had my Alpha it started just fine everyday. Then one day when I got off work I went to start it, nothing. I went to the dealer and they replaced it with a new factory battery. About two weeks later the same thing happened. This time I went and bought a Optima Red Top. It lasted for 3 weeks then it went dead. Took it to the dealer they didn'y find anything wrong with the trucks charging system and they shelled out the money I'd spent on the Optima. My new step was to replace the battery cables and get a Optima Yellow Top. This seemed to do the trick but a month later the battery was dead. No matter what I tried if the truck sat for more then 2 days the battery would go dead. My final solution was to add a onboard trickle charger and keep it plugged in all the time . It's a bit of a pain but I never have to worry about having a dead battery.

[navigator32v]

There was a service bulletin and maybe a recall on the factory battery. I'd ask the dealership. They replaced mine under warranty. The stereo may or may not be related. Also, H3's have rundown protection which can take power from other systems.

[wannabeH3]

i took a volt meter and took one of the cables off the battery then put one lead from the volt meter on the battery and connected the other lead to the cable I took off, then i think i set it to the milli amp setting for load testing. once you re-attach the power the computers boot up and whatnot for a good minute or two and you see the power draws up to an amp for that duration then it should go down a bit. Mine was pulling nearly 900 milli amps which is quite a bit and enough to kill it in 2 days. i was sure it was my radio that I installed and lo and behold it was the back up cam attached to my radio. I attached the accessory wire to a hot wire by mistake, and so it was always on. once i fixed it the load dropped to about 600 m-amps or something ... its been a year anyways battery is great now.

you can use that method and just pull fuses one at a time starting with radio and back up cams and **** till you find the significant drop in power consumption

[f5fstop]

Do what Drtyfn suggests!

[f5fstop]

Originally Posted by navigator32v

. Also, H3's have rundown protection which can take power from other systems.

Technically not true. Rundown ptotection does NOT take power from another system.

[wpage]

Make certain you remove the key from the ignition. Whenever the wife borrows my H3 she fails to key off all the way when leaving key in and it stays on and fries the battery overnite...

It seems like the key is off when in fact it is on. Over time it will lock up your ignition. The battery will be dead and you wont be able to even remove the key from the ignition.