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Battery issue: 2007 Tahoe LTZ = drains battery fast

Any help greatly appreciated. In 8 years, we’re on our 4th high quality battery. Our 2007 Tahoe LTZ just drains the battery and dies on us. Despite totally “baby-ing” the car (never leave lights on, ac off, and close automatic tailgate immediately), if we open & close tailgate or doors often (like when camping tho weekend), the battery dies. Local auto shops check our battery and say it looks full. It sounds like the car’s computer runs for awhile after we exit vehicle.

Any ideas? Can’t continue to buy a battery every 2 years.....

Thanks!

High quality batteries are warrantied for 5 years. You should get a free battery replacement if it fails in 2 years. Have the charging system checked as well as the cables going to the battery.

I put a yellow top in my 2009, IN 2009... and it's still in there!

I'd check to see what the drain on the battery is when the vehicle is off, there should be a way to measure that, but it's not coming to mind at the moment.

Welcome to the forum.
You need to measure the current draw on the battery with everything shut off. Then you need to start removing fuses one of the time until the current draw goes away.

Thanks, everyone. So this sounds like an issue with my car specifically, not a Chevy flaw (all the places I’ve been have told me that my year/model goes through batteries & oil like there’s no tomorrow).

Is there a recommended chain place or type of place that you think would be willing to check the fuses, etc?

Not sure I have the equipment or skills.

Taking it into service on Friday. $120 to test everything to find the draw.

Hopefully they find the source of it.

Body Control Module???

The shop had it for 5 hours today...running tests, trying to find what draining the battery and causing weird electrical/computer issues.

It all came up negative.

He did say that he thinks the body control module is the issue. I need a new one installed and programmed.

Any thoughts? Expensive? Need to have a pro do it?

Quote:

Originally Posted by ebiz1976 (Post 360921)

False, this is not a chevy flaw.
the vehicle needs to be check for parasitic draw. A draw over 50miliamps is excessive and needs to be traced. The first step is to disconnect any aftermarket devices. phone Chargers, aftermarket remote start modules. these devices may draw power or keep the factory modules awake. The factory system usually goes to sleep in under 5minutes(but it may take 20minutes) and draws 7miliamps once asleep.
Hard to comment on a shops diagnosis over the internet. It could be the bcm. It could be something the bcm powers.

If they are not a dealer, they can't replace or reprogram the module...this will have to be farmed out to a dealer for programming. the problem being, if the dealer does the work based on the shops diagnosis and it doesn't fix it...who responsible. Everyone blames the other guy. If the dealer diagnoses it, does the repair and it doesn't fix it...it on the dealer to fix it.

Having seen similar issues on my 07, I know this will sound very shotgun-ish but consider replacing both battery cables, I had several anomalies that would come and go with battery discharge that resolved when I replaced first the positive cable and then the negative. My cables looked fine but were making very poor connection at the eyelet/lug crimp connections. The chronic poor connections would allow the battery to not properly charge leading the battery failure after about 3 years.

good point...the cable can be tested by performing voltage drop tests. put your meter end at each end of the cable and measure the voltage with every electrical load on, vehicle running. should be less than 0.3 volts on the positive cable and 0.2 on the grd cable.