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2009 Hummer H3 Repair Question


Topics covered: Battery, Alternator, Engine.
Mileage: 19,780 miles.

Asked on September 23, 2011

Dead battery

Is it normal for a hummer left setting for 2 weeks to not start because of a dead battery.Thank you for any and all help.
Avatar Asked by marley123

Answer

Replied on September 23, 2011

The industry standard used to be most manufacturers would guarantee it would start after three weeks of non-use but the insane engineers keep on adding more and more unnecessary, unreliable computers with memory circuits that continually drain the battery. A few years ago some GM models could have up to 47 computer modules to do things computers weren't needed for before. If your truck starts after sitting for one week, that would suggest there is no unusually high current draw in the battery and no problem to diagnose.

Be aware though that many manufacturers have designed some of their computers to lock up and need to be unlocked or reprogrammed by the dealer once the battery was disconnected or run dead. Volkswagen and GM are at the top of that list of customer-unfriendly engineering. If your vehicle is not having any problems after it was jump-started, you either don't have any of those computers to worry about or the battery wasn't totally dead yet.

Tiny Answered by caradiodoc (expert)
17,643 answers provided
Replied on September 23, 2011

I would say it should start have you had the battery and alternator tested yet?If not thats the first thing you need to have tested.Also make sure where you have it tested the tester for the alternator also tested the diode in the alternator.Because if thats bad it can drain your battery.

Tiny Answered by saturntech9 (expert)
23,388 answers provided
Replied on September 23, 2011

The battery was new January 2011.The alternator is fine.I guess it must just be the damn computers.

Tiny Response from marley123
2 questions asked

Replied on September 23, 2011

Even though the battery is fairly new doesnt mean its good i have seen batteries new that bad only last a day month 5-6yrs etc.Never rule the battery out no matter how new.You can always do parsitic load test to make sure its normal and that you dont have excessive draw on the battery.I would also have the battery tested just to make sure.The alternator can charge good but if it has a bad diode it can drain the battery also.

Tiny Answered by saturntech9 (expert)
23,388 answers provided