Problems after dead batteries and jump start

[ashcraftd]

I have a 2008 Silverado 2500HD Crew Cab (LMM) with ~145k miles. Truck is all stock with 2 batteries and 2 alternators and I’ve had zero issues prior to this. I had a parasitic drain on the batteries that would periodically draw the batteries down, but never low enough to affect starting. The first indication of a low battery was the dual climate control would reset to 74/74. Recently the truck sat about a week and finally went low enough to not crank. I jump started at the passenger side battery and the truck started and runs fine. However, since that jump start, or maybe since the batteries went dead, I have the following 4 conditions, and no codes stored.

• Service 4 wheel drive in DIC
• Service Trailer Brake system in DIC
• ABS and Emergency brake lights on
• Park Assist System Off

I have searched and read many post about similar problems, but nothing identical. I haven’t found anything related to a jump start. I have already performed the following steps with no change:

• Disconnected both batteries for 1+ hour
• Checked all fuses in cab and engine compartment using a continuity tester
• Checked TREC fuse and removed/replaced it while key is on (Click sound when replacing it)
• Attempted TCCM re-learn multiple times with no success. No sound, movement or shift occurs
• Replaced both batteries with new identical H6 batteries

So far nothing has made any change. The truck runs fine and has no other issues. All of these conditions did not exist prior to allowing the batteries to go dead and/or jump start it.

 

[2004LB7]

sounds like a bad ground. maybe the one on the frame below the driver door

 

[ashcraftd]

Is there any reference to where all the ground points are? I have looked through everything on AllDataDiy and can't seem to find anything

 

[2004LB7]

let me know if you need anything else

 

[ashcraftd]

The source of the parasitic drain was located and eliminated. The battery type are the OEM H6 series and are both brand new since the dead / jump. I have not yet started to locate and check grounds. However, seeing as this started immediately after the dead batteries and did not exist before, I have a hard time believing that a bad ground condition suddenly developed.

Today I drove the truck about 45 miles. I had zero issues and it runs and drives great. However, these 4 conditions all still remain with no change in them at all. These did not exist prior to the initial dead batteries, so I have a hard time believing that they are real issues rather than faults due to the low battery condition. The OBD scanner I have can only read ECM codes. I'm curious if I had a better scanner which could read and clear codes in BCM, TCM and TCCM if this would resolve them. I expect that a dealer would start throwing parts at it based on the messages and lights.

 

[2004LB7]

I would find someone who has a scanner or purchase one that can read those codes. you could clear them and see if they come back

 

[Ron Nielson]

When your ABS brake light is on, that will also cause your Service Trailer Brake system in DIC to display. Fix the ABS system, the STBS message goes away also.
As for the other w messages, you might want to look at the wiring diagrams offered at https://www.gmupfitter.com/wp-content/uploads/2021/05/2008_LD_ElectricalPickupsChassisCabs.pdf

 

[ashcraftd]

You can't fix stupid. It was my own fault all along.

The cause of the parasitic drain was the BlueStar module I installed as a plug-n-play replacement for OnStar months ago. I unplugged it when I found the batteries were dead. My thought was that it was only OnStar/Bluetooth. But in reality, by disconnecting this I broke the GMLAN network. This was the problem the whole time. Unfortunately, it took several hours of labor for a shop to find that I had just left this disconnected behind/under the radio.

 

[2004LB7]

thanks for the follow up