Battery Drain 2008 Chev

[downslope]

Re: Battery Drain 2008 Chev--Solved??

... - people don't really realize the true cost of all these bells n' whistles...

So true, especially as a vehicle (or tractor for that matter) ages.

 

[Looking4new]

Re: Battery Drain 2008 Chev--Solved??

OK, problem is located but not fixed. Appears the malfunction is with the Sirius/XM radio and/or OnStar system. When I pulled the radio fuse current dropped much lower, maybe around 1 amp or less. Hard for me to tell exactly as I only have an analog ammeter. I also pulled the DIC fuse which supposedly also powers the OnStar. I was hoping for a simple problem like alternator, but apparently no luck.

These things are very hard to pinpoint without the right equipment and/or a lot of time. The diffferent modules (PCMs, BCMs, etc) continue to draw power even after you turn the key off. And then they will restart/reset after you disconnect the battery cable when you put the ammeter into the circuit. You have to get the ammeter in before you break the circuit, ie. you have to parallel the ammeter with a switch so that you never lose power to the modules. Some of the modules can require several hours to power down completely and go to "sleep". And then, even after they power down they can start up again, either by design or due to malfunction. Like OnStar, which will try to "call home" with your diagnostic report. This is all way too complex. Or the radio is designed to continue to play after you turn the key off until you open the door or a certain amount of time passes.
If you have the Verizon calling option with the OnStar it has to switch the speakers to the phone unit and silence the radio. It may be just a coincidence, but my battery trouble started right after I let the OnStar subscription lapse a month or so ago; who knows?

So now I'm completely frustrated and annoyed. I'm paying for a sat radio subscription but I can't leave the radio fuse in overnight. I was considering starting the OnStar up again, but now I'm thinking why bother.

Sorry this has been so long-winded but I feel I spent a lot of time on this and still no real solution.

I found and old TSB from back in June 2009 and they have you performing what seems like hours of testing with DVM and osciliscopes and then either reprograming the ECM or replacing the XM module. And this is only for the radio, similar things can happen with power memory seats, dual zone HVAC, fuel pumps, lift gates, etc, etc. I'll keep looking for more up-to-date repair documents.

How is the average guy supposed to fix something like this at reasonable cost? Have these systems gotten more reliable in the past 8-10 years, I hope so? Maybe those were lean times for GM designers back then?

The XM and radio have an on/off switch, just shut the radio off when you park.
Do you really need onstar?
The average guy is not supposed to be able to fix his new vehicle, he is supposed to take it to the dealer where he can get screwed again with their extremely high labour rates. That is on top of the screwing you took when you bought the truck to begin with.

 

[Diamondpilot]

Any updates?

Chris

 

[Industrial Toys]

Got a friend with a 2500 GM experiencing the same thing. It's driving him nuts.

Soon a five year old vehicle will be considered potentially too expensive to repair. Similarly with tractors.

 

[downslope]

Any updates?

Chris

Not yet. I've been having to use the truck a lot, just made a 700 mile round-trip to up near Oswego, NY/Lake Ontario helping some friends move household stuff with a trailer. When I got back I had to pick up a few pallets of cover crop seed, so the truck hadn't been sitting.

Before I left on the trip I put the fuses back and reactivated the Onstar subscription. I wanted to have the radio working and the hands-free calling for the trip (there is no bluetooth in the truck). No problems with being parked overnight those 4 days in 20 deg weather. So tonight is Wednesday and it's been sitting since Monday afternoon. Tomorrow is Thanksgiving, so I'll let is sit another day/night and see what happens on Friday. It would be something if the problem only happens when you let the Onstar run out!

I talked to a local mechanic friend and he said if the radio and/or BCM needs to be re-flashed or programmed only a GM dealer can do it. Does that sound right?

Let me ask you guys something. Back in 2008-2009 there were multiple TSB's about these problems:

TSB 09-08-44-001 : intermittent Dead Battery (reprogram radio),Feb 03,2009

TSB 06-06-03-013C : intermittent low battery voltage, engine will not crank (reprogram BCM) July 14,2008, plus others.

If it turns out it needs this reprogramming do you think I'll have to pay since the truck is long out of warantee or might they do it for no charge?

As an aside, missed this weather by a few hours after leaving Sunday night; heavy, wet snow off the lake, I guess:


I will update about battery drain when I find out more.

 

[downslope]

Any updates?

Chris

Just a (very) late followup on this. I paid to reactivate the OnStar and immediately all the battery problems went away. Still working good months later. Hope nothing happens when I transfer the XM satellite radio subscription to my new car next week.

I guess I can say I paid the money for OnStar instead of to the dealer for diagnosis! Maybe that's how they hold you captive!:laughing:

 

[k0ua]

Just a (very) late followup on this. I paid to reactivate the OnStar and immediately all the battery problems went away. Still working good months later. Hope nothing happens when I transfer the XM satellite radio subscription to my new car next week.

I guess I can say I paid the money for OnStar instead of to the dealer for diagnosis! Maybe that's how they hold you captive!:laughing:

Now that is a horrible thought. I was going to let my OnStar lapse

 

[4570Man]

I am having the same problem on my 2000 Chevy 1500. I tracked down the first culprit to be the door lock switch. I replaced it at the ridiculous cost of $80. Now, I'm having the same problem again. This time I'm pretty sure it has something to do with the power seat adjuster. My power seat adjustments and the power mirrors stopped working not long ago. Today I went to pull the fuse for the seat which was a 25 amp metal body fuse. It was so hot it burned my finger. I got a rag and pulled it out. I haven't finished trouble shooting the issue.

 

[dickfoster]

Thanks for all the suggestions, I will keep checking things out.
If fuel pump were running, would you be able to hear it by listening near tank?

Not really unless there is fuel flow. There is also a pressure regulator on the return side so the pump will normally stop running due to its internal pressure switch (or should) when the fuel rails get up to pressure. Not running means no fuel flow so pump gets up to pressure and shuts off.

All modern EFI vehicles have some parasitic current drain from the ECU, clock etc. measured in milliamps but 3 amps is far in excess. Keep yanking those fuses till you find the offending circuit and go from there. Hope it's not expensive.

 

[dickfoster]

Just a (very) late followup on this. I paid to reactivate the OnStar and immediately all the battery problems went away. Still working good months later. Hope nothing happens when I transfer the XM satellite radio subscription to my new car next week.

I guess I can say I paid the money for OnStar instead of to the dealer for diagnosis! Maybe that's how they hold you captive!:laughing:

That's when the Onstar crap would be ripped out and tossed into the trash can. XM? get an iPod or something. Yew don need no stenken XM either.