Dead again…

[dc968]

2023 Tahoe High Country Duramax (earlier thread) died after multiple warnings rotating through display. In shop for 3 weeks (local dealer was great), back and forth diagnosing w/GM, ultimately replaced electronic brake control module. Truck ran fine for 2 weeks, check engine light came on a couple of times, then front collision not available, then tonight full roster on warning messages, turn signals stopped working, got truck home and parked and now won’t start. Strike 2??

 

[StephenPT]

My gut tells me you have wire harness chafing and/or pin fitment/crimp issues. Tough problems to track down, but GM does have a TSB that highlights some of the common pinch/chaff points on all their engines, including the Duramax. I’ll dig it up and post it soon.

 

[StephenPT]

https://static.nhtsa.gov/odi/tsbs/2021/MC-10205552-9999.pdf

 

[dc968]

Thanks for posting the link. Does it apply to 2023 models as well?

 

[UsualSuspect]

I must be really behind the times. I would think a brake control module takes care of the brakes, but I guess not. I hope they find the issue, maybe a bad battery? For some reason dead batteries tend to bring out the worst in electronics these days.

 

[dc968]

Battery was dead this am and wouldn’t respond to jump box. Flatbed back to dealer.

 

[Tiredmechanic23]

I must be really behind the times. I would think a brake control module takes care of the brakes, but I guess not. I hope they find the issue, maybe a bad battery? For some reason dead batteries tend to bring out the worst in electronics these days.

It used to be that way but modern cars have everything on CAN networks talking to each other and if a module fails it can potential drag down every other module with it until it is replaced. It can make for fun diag work. I work in heavy equipment and its the same way in that field now as well and while its not an all the time thing to see happen it still happens enough to get annoying.

 

[DuraYuk]

Check battery voltage while running. Wonder if alternator is failing.

 

[dc968]

Update: service rep called today and said they replaced battery and everything is functioning as should. Tech drove home last night and back again this am w/no issues. They’re keeping it for the weekend and will retest everything on Monday.
One question is that they claim to have tested battery the first time the rig crapped out and it wasn’t a problem. This time, same issues but now it’s the battery??

 

[CMoore711]

Yeah they for sure “tested” it the first time…