Intermittent dead battery in the AM ! '04

[Joe Valle]

Great '04 Tahoe . Had this Tahoe almost 3 years & been dealing with battery drain down to 4v this AM . Months (6+) mo or this time (2) times in a week . In my reading in the past I’ve run across ABS controller as interment problem . I replaced he ABS controller for abs failure . i know this does not mean this controller not still suspicious. Having been a professional Mechanic in another life I know every vehicle has its standard repair problems as they get older . What does this site consider the top (10) causes for this type of battery drain . Thanks , Joe

 

[MassHoe04]

From what I have seen, bad grounds might be one of the top 10 battery drain factors.
Bad ground connections can prevent things like the BCM from turning things off fully after the designated programmed amount of time. Things like radio/HVAC and others are allowed to 'sleep' but don't fully shut off.

 

[Fless]

It wouldn't hurt to do a comprehensive parasitic draw test after the battery's been load tested and cleared. Clean battery and cable terminals, and ensure the main grounds are clean and cables are good.

Not recommending throwing parts at it, but some causes are:
1. Driver's door latch (as in RAP not turning everything off after the appropriate timeout)
2. Instrument panel cluster (search this site or Google 'chevy silver migration')
3. Note that the AUTO HVAC head, if yours has it, can take several hours to fully sleep
4. Aftermarket alarm, remote start, or radio, depending on how it was wired
5. Dirty PCM connectors; remove, inspect, and clean both (added as an edit)

I'm sure we'll think of some others, but those are some common causes. Plenty of good YouTube videos on parasitic drain diagnosis. These trucks routinely draw 20-30 milliamps after fully asleep. If yours is anywhere north of 50mA, time to dig into it. If you need some suggestions, sound off.

 

[Donal]

Great '04 Tahoe . Had this Tahoe almost 3 years & been dealing with battery drain down to 4v this AM . Months (6+) mo or this time (2) times in a week . In my reading in the past I’ve run across ABS controller as interment problem . I replaced he ABS controller for abs failure . i know this does not mean this controller not still suspicious. Having been a professional Mechanic in another life I know every vehicle has its standard repair problems as they get older . What does this site consider the top (10) causes for this type of battery drain . Thanks , Joe

The ignition key needs to be removed to allow the body control module to put everything to bed. My son had to have a explanitaion of this. You probably already knew it.

 

[Joe Valle]

It wouldn't hurt to do a comprehensive parasitic draw test after the battery's been load tested and cleared. Clean battery and cable terminals, and ensure the main grounds are clean and cables are good.

Not recommending throwing parts at it, but some causes are:
1. Driver's door latch (as in RAP not turning everything off after the appropriate timeout)
2. Instrument panel cluster (search this site or Google 'chevy silver migration')
3. Note that the AUTO HVAC head, if yours has it, can take several hours to fully sleep
4. Aftermarket alarm, remote start, or radio, depending on how it was wired

I'm sure we'll think of some others, but those are some common causes. Plenty of good YouTube videos on parasitic drain diagnosis. These trucks routinely draw 20-30 milliamps after fully asleep. If yours is anywhere north of 50mA, time to dig into it. If you need some suggestions, sound off.

 

[Joe Valle]

Thanks for the feed back . I know from my past professional life that Intermitant electrical amp draws are a ***** . Twice in a month or once every (6) months is a tough on to find . What have real people found ?? Thanks , Joe

 

[pauly1119]

I’ve actually solved this same problem by added new grounds in the past. I used left over golf cart wires.

 

[Fless]

Thanks for the feed back . I know from my past professional life that Intermitant electrical amp draws are a ***** . Twice in a month or once every (6) months is a tough on to find . What have real people found ?? Thanks , Joe

This real person found that his driver's door latch was intermittent. Happened a few times a month.

 

[rockola1971]

First check that all light inside the vehicle are turning off like they are suppose to be shortly after last door is closed (about 30 secs).
Then immediately check the engine ground between the rear engine block and the firewall. This one is braided and breaks at one end or the other OR just gets totally corroded and no longer conducts, also check for corrosion at the bolts/nuts on each end.
Check ground under drivers side door on frame rail up near firewall. Check for broken wire, corrosion on wire and at end terminals (Bolts/Nuts).
Wouldnt hurt to put battery on a charger until fully charged and take into a auto parts store to be load tested.
Verify your alternator is charging via a voltmeter with engine running or atleast using the dash voltmeter.
BCM not going to sleep possibility which can be a number of things including the bad grounds. If the BCM loses its ground reference then it throws up and doesnt know what to do.

 

[theo robertson]

I experienced the same problem on my 2005 Denali and for me it ended up be the instrument cluster.