Truck forgot all Keys

[Yellow05gt]

Has anyone ever had this problem? It's a 2021 AT4 3.0L Duramax.

The truck was running fine that morning. Got home and was only there for about 30 minutes. Went backj out and the truck wouldn't turn on. Kept saying to put the key in the pocket. So i did that. Nothing. Then i heakd the brake and the push button start and it started saying ready for remote 1. Apparently the truck deleted all memory of the key. I had to have it towed to the dealership last tuesday and they cant figure out what is wrong with it. As of Friday, they sent a request to GM engineers to help figure it out because they say they've never seen this happen. Any insight would be greatly appreciated!

 

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[gemarsh]

It won't re-learn your keys?

 

[Yellow05gt]

Nope. And nothing the dealership has done so far can get it to learn them.

 

[Ohiost90]

wow...sounds like the truck got bricked some how. good luck.

 

[adeerchaser]

Now that has pegged the dammit meter! Good Luck!

 

[Teegunn]

Holy crap, that is a scary problem!

I am working out of state (again) 1000 miles away from home, and I forgot my 2nd key fob at home in Montana (am currently in Nebraska working). I am constantly worried about losing my sole key fob I have for my truck, because it would mean a trip to the dealership for what I am guessing would be a $400 key fob if I were to lose the one I have with me.

But your problem sounds much worse. Like wtf worse. I hope they get if figured out quickly for you!

 

[Ohiost90]

for lost keys, these have been a game changer for me

 

[Yellow05gt]

Thanks. As of today, haven't heard anything else. Oh and to top it off they did tell me Friday they are hoping GM covers this under warranty. They said they may not because I have train horns installed. I told them they better prove the one accessory wire I have plugged into the fuse box causeed the issue. If not they better be footing the bill.
@Ohiost90 I also use Airtags on my keys so I am in the same mindset as you for sure. Great idea

 

[Ohiost90]

They said they may not because I have train horns installed. I told them they better prove the one accessory wire I have plugged into the fuse box causeed the issue. If not they better

That is ridiculous. The idea that anything into the fuse box to draw a few amps would brick the truck is over the top. It would be almost believable if it was a turner or something similar plugged into the OBD. Hope good news is on the way soon.

 

[Yellow05gt]

That is ridiculous. The idea that anything into the fuse box to draw a few amps would brick the truck is over the top. It would be almost believable if it was a turner or something similar plugged into the OBD. Hope good news is on the way soon.

Exactly my thoughts too. They replaced the BCM and it’s still having the same issue as of today.

 

[Joemiles79]

Did you ever resolve the problem? Cause I’m having it with the exact same truck/ engine. Thanks in advance.

 

[Island Dan]

Keep bugging your dealer, GM is well aware they had a bad batch of bad BCMs. My wife's 2021 GMC had three go bad and brick her car.

 

[Joemiles79]

Keep bugging your dealer, GM is well aware they had a bad batch of bad BCMs. My wife's 2021 GMC had three go bad and brick her car.

Yep! That’s exactly what they are telling me now. That it’s the BCM, and somehow I caused the error in it. Now it’s a problem for next week, to fight them on it. If you have any documentation of what happened to yours, I’d appreciate seeing it. Thanks.