battery drain

[dna]

Have a '03 H2 - had it about 4 years now. Practically since I had it, I had a dead battery all the time. It was under warranty for the first few years and I had it checked, but they found nothing. Though I would still get a dead battery every few months.

I found that if I put a new battery in, I would get a good 3 months of no problem, and then it would start. It would be irregular.

I eventually installed a battery guard which cuts power when the battery gets to a dangerous low voltage. This works great to prevent me from having to jump it, though it does get old - having to override the battery guard almost every 2nd day.

So, my questions are:

1) if I put a multimeter in line, what is "normal" drain when in 'off' position
2) I've heard that many other H2 had this same problem - what are the typical causes.

BTW - I do not have many custom electronics - most is stock.

Thanks

[HummerJim]

After market lights, sound or nav are the first places to look. There are some earlier posts (summer of 2005?) about the ignition module grounding to the steering column with a slight drain.

[working Hummer]

Good luck with this! I had an aftermarket GPS system put in and had a dead battery every 2 days, so I spent hours upon hours tracing this problem out because the stereo shop said it wasn't their unit causing the problem. You will have to pull 1 fuse at a time to find the draw. If I remember right on the Hummer you want to be around 20-40 mA (.02-.04) to be OK. I was at 181 mA (.181) and that was a problem. I eventually found out my factory Bose amp was not shutting down. Fixed that and droped to 49 mA but still had a dead battery problem. Go to find out that the stereo shop drained my battery to dead and recharged for a bit and drained to dead again and again, so got a new battery and haven't had a problem since. Good luck!

[lasvegash2]

my brothers 2007 does the same thing. he has had is for about 3 months now and on the second battery...his is stock. the dealership keeps on putting a new battery in and doesnt want to look for the cause.

[H2Much]

It's the aftermarket deck, or anything in relation to it, that is for sure. I am having the same issue and so is everyone else I know. The dealership said that the battery in there is just not big enough to handle current from any additional stuff besides the stock stuff. They suggested to get a Gel battery, or a group 76 battery, and that should fix it.

When you add stuff, they have to put in a databus system that communicates with your factory stuff, kind of liek a computer that interconnects your aftermarket stuff with the bose amp and everything in the car that runs through the amp. This is where all the problems start. You would think after making these things for the last 6 years, and as advanced as man is, that they would be able to fix this, or at least communicate a fix to the owners of it, since the vehicle is supposed to be a "utility" vehicle. Stupid engineers.

I haven't hear of checking the Bose amp, like the guy said above, so I am going to be looking into that as soon as I get mine back. I am sick of messing with dead batteries, and I am going on 2 years with that problem.

[Pure_Justice]

There are so many ways to tackle this issue I don't know where to begin.

You stated that you didn't have any additional electronics after market items on your Rig, which means that you have nothing else pulling any additional load.

So, that means we have to assume that the battery circuit can provide sufficient current for all components. That being the case, each component has diodes which limits and reduces the return voltage going back to the battery circuit. Given that, and given that this is a new issue from when you purchased the vehicle, one of your electrical parts is going bad, somewhere.

Like one of the other members mentioned, try removing individual fuses. Usually start with the radio, then work towards any dealer installed options.

Just as a sanity check though, you want to make sure that the alternator is working first, before the removing fuse excersise. Something is going bad in one of your components, and installing a battery with more juice is only buying you more time, not solving your issue.

Remember, all electrical circuits, including the battery circuit have a designed resistence and load capacity. Change any of those variables and you run into problems like theses as well as circuit cards going bad.

Additionally, if the dealer did a diagnostic on your Rig, and found no issue, then you are safe in assuming that the master circuit card is still working, as the diagnostic would have surely picked it up. So now the issue is elsewhere.

To really troubleshoot this correctly you need a schematic, which only the dealer can provide. But try removing individual fuses, that may guide you to your source problem.

Sorry this is so long winded.

Good Luck

[giant h2]

Originally Posted by working Hummer

Good luck with this! I had an aftermarket GPS system put in and had a dead battery every 2 days, so I spent hours upon hours tracing this problem out because the stereo shop said it wasn't their unit causing the problem. You will have to pull 1 fuse at a time to find the draw. If I remember right on the Hummer you want to be around 20-40 mA (.02-.04) to be OK. I was at 181 mA (.181) and that was a problem. I eventually found out my factory Bose amp was not shutting down. Fixed that and droped to 49 mA but still had a dead battery problem. Go to find out that the stereo shop drained my battery to dead and recharged for a bit and drained to dead again and again, so got a new battery and haven't had a problem since. Good luck!

what is the radio amp fix?

[pdxrealtor]

A couple of threads on this.

Get the priority start and be done! Less than a 100 dollar bill. I got mine from battery stuff at the recommendation of the manufacturer, because they're close to where I live.

[pdxrealtor]

I meant to take pics today, of the priority start installed, but ran out daylight. I'll try to get them on here.