19Sierra

That sucks, mines been good so far, fingers are still crossed though. Lol there was another guy at the dealer Wednesday that was having the same issue as us. So clearly it's not a couple isolated incidents.

So the light went out on my way there but the code was still saved in the truck for that ignition cycle. Here's what they did this time. Hopefully this fixes it, but only time will tell.

Was your 4wd light intermittent as well? Did it clear itself after driving a few miles?

Light came on again when I pulled into my driveway. Hopefully the light stays on for the trip to the dealership tomorrow morning. Would have taken it right there but they said they dont have any loaners available or anyone to give me a ride to get a work truck.

Thank you for your knowledge. Now I just have to try to get the truck to the dealer next time it comes on before it clears itself.

The code that was originally pulled the first time I took it in was C15A9. Is that similar to the codes you've seen on the trucks that came in?

Light went back out after driving for 10 miles. Called dealer this morning and they told me unless the light is on there is nothing they can do. Starting to get really frustrating.

Have you found a fix for it?

Well the service 4wd message just came back on for me again when switching back to 2wd. Truck was moving this time when it did it. Called onstar and they said there are no faults or codes showing. Not sure how as the service 4wd message is displayed on the dash. Guess I get to call the dealer again about it tomorrow.

Sounds like your issue is different than mine was. Hope you get it figured out. Next time the light comes on call onstar and see if they can tell you what the code is. Good luck

Does the light come on when selecting a different range in the transfer case or when driving around in the same range? My service 4wd light would come on when switching back to 2wd after pulling into the garage. I would back in select 2wd than shift the truck Into park and shut it off. It seems that if you are too quick and shift gears or shut the truck off while the transfer case is still selecting a different range it can sometimes throw a false code. I actually found an article on gmtechlink about this issues. https://gm-techlink.com/?p=11123 Since reading this article I have been mindful to not shift gears or shut the truck off until the transfer case has finished selecting and I havent had any issues yet. I had mine at the dealership twice for this. The first time I got the light to come on when pulling in. The code read sensor position not plausible. The second time the light went away and they couldnt find any stored codes in the truck. Onstar even said there wasnt any codes in the truck either even though when I called them the service 4wd light and message was on.

I didnt have any issues with mine after having the recall done. I also never used the app to start the truck either. I'm afraid to even try using the app in case it causes me to lose my brakes ( I have been using the key fob alot though). I wonder if gm will let everyone know that there is a software update available to fix the issues that some are having after the recall or if it only applies to those that have had the lost brakes issue.

Looks like the frame is bent as well by the way the whole truck now has a dip in the middle. Some heatin and beatin and it should straighten right out. Lol

If GM knows the app is causing the problem than you would think GM would dissable the app for the time being until they work the bugs out! I guess that $14.99 is too important to them. Lol I have been following this issue since I had the recall done (12-19-2019) to my 19 elevation. I have not had any of the problems you guys have had (knock on wood). I also have not used the gmc app to start the truck either. I have only used the fob or the push button in the truck. After reading these issues I will be certain to not use the app.

I was referring to the messaging app a poster mentioned above. Regardless the only way for texts to show up on my Info screen is if I am plugged into android auto and have android auto pulled up on the Info screen. I am using a galaxy s9. Build date is 7/19.