I have a 1997 H1 that's been having problems starting. The battery is new and I made sure that it was the proper battery for my H1 (Optima) before I had it installed. If I leave it alone for a few days, the engine won't start. I have to recharge the battery every time I want to start up the Hummer. I've swapped out the old PMD for a new one. I've had someone look at the alternator to see if that was the problem, but it wasn't. I've had someone disconnect all the radio and audio equipment that came with the car as well as the door chime to see if it would help stop the power drainage, however, the symptoms still continue. Of note, the lights and fuel pump are all working but the battery doesn't have enough power to start up.

If anyone has any experience with this type of problem or advice for me, I would greatly appreciate your knowledge. Thank you!

 

My new Optima's were about 6 months old when I used my offroad lights all night the next thing I know the rig will not start. the Optima Dealer check and found a bad cell in one of the battary they replaced it and no problems since.

 

Linda it sounds like you have done all the obvious things.