I have had this happen to me twice now. If I don't drive the H2 for a couple of days, the battery dies. I have had the battery checked out and everything reads fine, so something is obviously draining it while the car is off. I don't mean it gets low and won't crank, I mean it get's so low the interior lights will barely even glow when you open the door.

I did a search and saw some people having issues with the ignition switch and the radio etc won't turn off, but that's not the case with mine. Everything is off. I do leave my radar plugged in, but that can't be drawing enough to drian the battery, as I have done it in other cars with no issues.

I do leave the keys in the ignition, but the ignition is fully off. Should I not be doing this? Does it keep the "brain" on and possibly drain the battery to even have the key in there?

 

Why don't you try the following:
1. Take the key out for a couple of days
2. Unplug the Radar detector for a couple of days
Did that solve the problem? If not then post back

 

I was hoping somebody might have gone through something similar and I could avoid killing the battery every time I try to eliminate something from the possible causes.

 

I had that same problem, and the solution is to remove the onstar fuse from the fuse box. Onstar drains the battery while the vehicle is turned off, try that, I guarantee you it will work. I had that problem for 1 year and a half, and a friend who also had that problem found that out, told me, I tried it, and it worked like a charm.

The fuse you need to remove is the one highlighted in this image:

http://www.hummerxclub.com/forum/dow...le.php?id=7876


Come back a few days from now, and tell me it worked, cause it will

 

Perfect! I'll definitely give it a shot. I'm not an OnStar subscriber though. Is it still "on" and pulling power anyway?

 

Yeah, it's still pulling power even if you are not subscribed. In the country I live that service is not available, and so far 3 people here had that problem, and removing the onstar fuse solved it.

Let me know later if it worked for you too.

I was going mad with the battery drains also, 1 year and half having that problem, and I just had to remove 1 little fuse of something that I didn't even use. lol

 

I pulled it Monday night after I saw your post. The weather really depends if I drive it much. If we have nice weather and it sits all this weekend, I'll get to see if it worked!

Thanks again!

 

you need to turn off the interior lights with the little overide button[ by the switch] so the lights dont come on when you open the door and try that let me know if that helps .

 

My hummer does this also thats funny. It takes about a week for it to happen thoe. Thats what my buddy tells me since I am deployed at the moment.

 

fwiw,,normal drain for,,h3 is 110 ma, or 1/10 amp.
its really quite a bit if just left sitting. disconnect or use a small trickle charge huh?