Please help! After sitting in the garage for about a month, my 2007 hhr's alarm suddenly started going off. I had to leave the key on the acc position to get it to stop, which drained the battery. After recharging the battery the vehicle would NOt start, but I had dash lights, door chimes and a 'engine at reduced power' while NOT running. I tried disconnecting the battery for 10 min to reset everything, tried making sure the fuses etc were tight, and now have no electrical power at all. No start, no lights, no displays, no door chimes, nothing at all. Help me!!

 

Sounds like a dead battery to me. Did you have the battery tested? Charging a dead battery does no good whatsoever. The only other thing I can think of is varmints have taken up residence and eaten some wiring.

 

Get a known good battery and see if it starts. If not you may have some electrical sleuthing to do.

 

Yes, this is brand new battery holding a full charge. One new symptom, the CD player will light up and accept or eject a disc, but will not play and shuts off right away. This the only electrical I have. Could this be a security lock-out cause by low battery? What to do? Stupid complicated computerized crap

 

Security lock out gets fixed the first time you use the key. Sounding more like varmints in wiring, more than one report of rats/mice/squirrels in the waterfall. I don't know why a BCM would go bad from sitting, but that's a possibility.

 

I'd still suspect the battery - even new ones fail - I'd swap to a known good battery, or have your autoparts store throw it on a load tester to double check it.

Any sign of those pesky vermin around where the car is stored?

I've had them eat sparkplug wires before - luckily not much further damage.

 

Battery is totally fine, both the old one and the new one. No varmints, vermin. Just no power. Turn key (have tried both keys) and nothing. No dash lights, head lights, wipers, just nothing. All fuses seem fine and are seated properly.

 

Sounds like time to get the volt/ohm meter out and start checking from the battery forward to under the hood, then the dash. Both power and grounds need to be checked.

Some people have had problems with the fuse block under the hood having bad connections - you might want to check that out first.

 

I don't remember, did you check the maxi-fuse in the back near the battery, it looks like it is attached to the negative cable.

 

maxi fuse is fine...retried both batteries and still nothing. no lights....nothing. I am so frustrated.