2006 Yukon Denali Parasitic Battery Drain

[Phil Van Beveren]

Been fighting this for about 2 months.. Battery holds up for about 6-8 hours while sitting at work, 9 or more hours sitting over night and the battery is dead enough it won't start the truck. Replaced starter, no help, pulled alternator and had it tested and it is good and meets all standards. Also replaced the battery in April of this year.

Put an amp meter between negative cable and negative post on battery (in series) and it shows about a 2.5 amp drain. Started pulling fuses. The radio and radio amp fuses reduce the drain by about 0.9 amps so don't think this is it... Pulled the TBC2 (Truck Body Control) fuse and drain reduce by over 1.5 amps... think this might be it.

I have had some minor issues with the Body Control Module but disconnecting the battery for about 5 hours and letting all the energy drain out of the BCM cured the problem.

Any thoughts or ideas on where to look next now that i know it's in the TBC circuit somewhere would be greatly appreciated.

Regards

Phil

P.S. I installed a cutout switch between the negative battery cable and the negative battery post to stop the drain so i don't need a jump start every morning.

 

[OR VietVet]

Gobs of years ago the allowable draw was around 30 milliamps. Now it is up around 140 to 150 milliamps. I think your left over draw reading of 1 amp is still too much. Did you measure the draw if you unhook your alternator? Diode problems can cause the draw to be excessive but would/can still show charging ok.

 

[swathdiver]

Been fighting this for about 2 months.. Battery holds up for about 6-8 hours while sitting at work, 9 or more hours sitting over night and the battery is dead enough it won't start the truck. Replaced starter, no help, pulled alternator and had it tested and it is good and meets all standards. Also replaced the battery in April of this year.

Put an amp meter between negative cable and negative post on battery (in series) and it shows about a 2.5 amp drain. Started pulling fuses. The radio and radio amp fuses reduce the drain by about 0.9 amps so don't think this is it... Pulled the TBC2 (Truck Body Control) fuse and drain reduce by over 1.5 amps... think this might be it.

I have had some minor issues with the Body Control Module but disconnecting the battery for about 5 hours and letting all the energy drain out of the BCM cured the problem.

Any thoughts or ideas on where to look next now that i know it's in the TBC circuit somewhere would be greatly appreciated.

Regards

Phil

P.S. I installed a cutout switch between the negative battery cable and the negative battery post to stop the drain so i don't need a jump start every morning.

Welcome to the forum Phil. Each body style has an acceptable parasitic drain as even when the vehicles is shut off, computers come alive to communicate with this and that and to run tests. a scan tool may show you where the drain is coming from but it seems to me you've already identified the culprit.

 

[OR VietVet]

I know I have been out of shops for a while now but when he unplugged the TBC and the parasitic draw went from 2.5 amps to 1.0 amp that equals a 1000 milliamp draw and am I to believe that amount of draw is acceptable? I am not saying you are wrong but to this old man that seems like a way out there amount of parasitic draw. 1000 milliamp is gobs. Please educate me on what I may not be understanding.

 

[Wylie_Tahoe]

Been fighting this for about 2 months.. Battery holds up for about 6-8 hours while sitting at work, 9 or more hours sitting over night and the battery is dead enough it won't start the truck. Replaced starter, no help, pulled alternator and had it tested and it is good and meets all standards. Also replaced the battery in April of this year.

Put an amp meter between negative cable and negative post on battery (in series) and it shows about a 2.5 amp drain. Started pulling fuses. The radio and radio amp fuses reduce the drain by about 0.9 amps so don't think this is it... Pulled the TBC2 (Truck Body Control) fuse and drain reduce by over 1.5 amps... think this might be it.

I have had some minor issues with the Body Control Module but disconnecting the battery for about 5 hours and letting all the energy drain out of the BCM cured the problem.

Any thoughts or ideas on where to look next now that i know it's in the TBC circuit somewhere would be greatly appreciated.

Regards

Phil

P.S. I installed a cutout switch between the negative battery cable and the negative battery post to stop the drain so i don't need a jump start every morning.

How long did you let the setup sit, before recording that draw? Not uncommon for modules to wake up after after a power re-connect and have a high amp draw, before going back to sleep. So a 30-60 min wait before taking an amp draw reading is a good idea.

IMO, that stereo draw is excessive, if its continuous, as in still there after some time.

 

[Mr. 960]

try the IPC fuse. Instrument panel cluster fuse. IPC is known to go bad by not going fully to sleep and will continue to draw current. Just a guess.

 

[Phil Van Beveren]

Gobs of years ago the allowable draw was around 30 milliamps. Now it is up around 140 to 150 milliamps. I think your left over draw reading of 1 amp is still too much. Did you measure the draw if you unhook your alternator? Diode problems can cause the draw to be excessive but would/can still show charging ok.

I removed the alternator and had it tested and made sure they test the diode pack as well.

 

[Phil Van Beveren]

I know I have been out of shops for a while now but when he unplugged the TBC and the parasitic draw went from 2.5 amps to 1.0 amp that equals a 1000 milliamp draw and am I to believe that amount of draw is acceptable? I am not saying you are wrong but to this old man that seems like a way out there amount of parasitic draw. 1000 milliamp is gobs. Please educate me on what I may not be understanding.

I just shared the readings i got. Not saying the draw from the radio and radio amp is acceptable at all.

 

[OR VietVet]

I don't think the alternator diodes can be tested off the vehicle. I could be wrong but way back you tested on the vehicle.

 

[Phil Van Beveren]

I don't think the alternator diodes can be tested off the vehicle. I could be wrong but way back you tested on the vehicle.

It was connected to their test machine and they were tested according to the technician that was helping me.