Acobrajet321
TYF Newbie
- Joined
- Jun 24, 2021
- Posts
- 10
- Reaction score
- 15
A few weeks ago my 2011 Yukon XL, SLT 2wd 'went haywire' while pulling away from a stop light after having been driving 45 min. The kids jokingly said it was haunted . The locks locked/unlocked erratically without any input. The transmission would not shift. I ended up pulling over to shoulder. Turned the truck off, waited about a minute, turned it back on and it was 'normal' again. Got on the forum and read that similar situations have occurred with transmission control modules and body control modules going bad. AllData DIY had GM Service Bulletins with a list of solutions to everything from frayed wires, loose connections and DTCs that would be logged. I had no DTCs....in any module.
I chewed on it for a while and realized I'd been having some other electrical 'ghosts' for the past few weeks. I noticed 'flickering' in our LED fog lights when stopped behind cars in traffic. Our HVAC control module kept resetting to factory default settings (74 degrees driver and passenger). When we would sit in a parking lot with just accessory power, we would get an info message of "low battery - start engine" within 2-3 minutes. I checked the alternator and battery. Both were in good working order. Battery had a state of health of 84%. It definitely shouldn't have been drained in 2-3 minutes of listening to the radio.
While testing the battery I noticed corrosion on the battery terminals. Cleaned with baking soda solution/old tooth brush. As I was doing that, I noticed the cable itself had corrosion. I decided to replace the cable. Found a Genuine GM on RockAuto.
It took me about 45 min to swap out. FYI there is a smaller ground on the frame behind the front right bumper cover. You have to remove wheel well splash guard to get to the 10mm bolt holding it in. Not hard once the splash guard is pulled out of the way.
Once it was back together, the Yukon started with noticeably more pep, it sounded stronger and started quicker. It's been a month now and have not had any more of the 'hauntings'.
My wife has sat multiple times for an hour plus listening to radio while kids are in activities without the 'low battery" message. I've also noticed the DoD transfer is a lot smoother, there was a shudder when transitioning from V4 to V8 and that is now gone.
Wanted to post this as a possible solution for others, if you notice corrosion, I'd start with a new negative cable and 45 min in the garage before throwing $$$$ at diagnostics and control modules. (I will qualify, if you're getting DTCs in the module it may be more than just voltage drop. You may want to start looking there for frayed wiring/loose harness connections as GM had quite a few service bulletins. Sounds like that may also be a common problem).
I've attached some pics of the corroded cable and one compared to the new cable. I'm betting there was definitely some voltage drop because of the corrosion causing my 'ghosts'
.
I chewed on it for a while and realized I'd been having some other electrical 'ghosts' for the past few weeks. I noticed 'flickering' in our LED fog lights when stopped behind cars in traffic. Our HVAC control module kept resetting to factory default settings (74 degrees driver and passenger). When we would sit in a parking lot with just accessory power, we would get an info message of "low battery - start engine" within 2-3 minutes. I checked the alternator and battery. Both were in good working order. Battery had a state of health of 84%. It definitely shouldn't have been drained in 2-3 minutes of listening to the radio.
While testing the battery I noticed corrosion on the battery terminals. Cleaned with baking soda solution/old tooth brush. As I was doing that, I noticed the cable itself had corrosion. I decided to replace the cable. Found a Genuine GM on RockAuto.
It took me about 45 min to swap out. FYI there is a smaller ground on the frame behind the front right bumper cover. You have to remove wheel well splash guard to get to the 10mm bolt holding it in. Not hard once the splash guard is pulled out of the way.
Once it was back together, the Yukon started with noticeably more pep, it sounded stronger and started quicker. It's been a month now and have not had any more of the 'hauntings'.
My wife has sat multiple times for an hour plus listening to radio while kids are in activities without the 'low battery" message. I've also noticed the DoD transfer is a lot smoother, there was a shudder when transitioning from V4 to V8 and that is now gone.
Wanted to post this as a possible solution for others, if you notice corrosion, I'd start with a new negative cable and 45 min in the garage before throwing $$$$ at diagnostics and control modules. (I will qualify, if you're getting DTCs in the module it may be more than just voltage drop. You may want to start looking there for frayed wiring/loose harness connections as GM had quite a few service bulletins. Sounds like that may also be a common problem).
I've attached some pics of the corroded cable and one compared to the new cable. I'm betting there was definitely some voltage drop because of the corrosion causing my 'ghosts'
.
