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Posted
On 4/8/2024 at 5:50 PM, BringTheRain403 said:

One week in and so far so good.  I'm more and more optimistic by the day

Not sure how I didn't see this before. That's good news. My master switch came, but I'm holding off until ,god forbid, it happens again. Mine has been fine so far. I'll keep you posted 📫

 

 

  • 3 weeks later...
Posted

So I am having this same issue.  I put the xtool D7 and I get this coming from the BCM. I am having 3 of the several BCM failing/BCM going out symptoms. 

I have a 2021 2500hd Duramax and I have had to be towed home and I have successfully got the truck started 2 times in the past 2 weeks but always too late to bring it to the dealer or i had to go to work for a call out and i had to take my other truck due to not trusting this truck. This is some b.s.  I have 0 faith in GM anymore.  They have over complicated the hell out of these trucks. my truck was stuck with parking  break engaged and no way to remove it.  Tow truck driver had to literally drag the freaking  65k truck  on his flat bed. When I eventually got the truck started I immediately removed the parking break so that isn't am issue for the next time I have to get it towed which is probably today. 

 This design to not allow insering a key inside the truck and over riding the electronics that are clearly a problem. GM clearly thinks their engineering  is better than it actually is. Absolutely no work around for when their products. No wonder they don't hardly give you a warranty. I guess they don't trust their own products now that I think about it. 

Sorry for the rant I'm just extremely frustrated I've spent nearly 600 dollars just trying to get the truck to the dealer to get it fixed. 

20240423_191545.jpg

  • Like 1
Posted
4 minutes ago, Daniel Rey said:

So I am having this same issue.  I put the xtool D7 and I get this coming from the BCM. I am having 3 of the several BCM failing/BCM going out symptoms. 

I have a 2021 2500hd Duramax and I have had to be towed home and I have successfully got the truck started 2 times in the past 2 weeks but always too late to bring it to the dealer or i had to go to work for a call out and i had to take my other truck due to not trusting this truck. This is some b.s.  I have 0 faith in GM anymore.  They have over complicated the hell out of these trucks. my truck was stuck with parking  break engaged and no way to remove it.  Tow truck driver had to literally drag the freaking  65k truck  on his flat bed. When I eventually got the truck started I immediately removed the parking break so that isn't am issue for the next time I have to get it towed which is probably today. 

 This design to not allow insering a key inside the truck and over riding the electronics that are clearly a problem. GM clearly thinks their engineering  is better than it actually is. Absolutely no work around for when their products. No wonder they don't hardly give you a warranty. I guess they don't trust their own products now that I think about it. 

Sorry for the rant I'm just extremely frustrated I've spent nearly 600 dollars just trying to get the truck to the dealer to get it fixed. 

20240423_191545.jpg

It's not a rant, it's the unfortunate truth. Luckily, so far, whatever they did on th TSB has worked for me. I drive it every day and it's been fine. I haven't taken it on any longer trips since, but it gets driven. The one thing they did that had me wondering was the extra ground. I'd never heard of that as a fix, but who knows? The times it happened to me I was able to disconnect the battery and it was fine. I hear alot of people have put a Battery Tender on theirs. I did purchase an extended warranty a few weeks back, just for peace of mind. Good luck. If I find anything else out, I'll let you know.

 

Chris 

Posted

Thanks man, I'm trying to get it to the dealer right now...last week tow company broke their cable trying to drag it and their other truck had engine problems. Appreciate the reply. 

Posted
20 minutes ago, Daniel Rey said:

Thanks man, I'm trying to get it to the dealer right now...last week tow company broke their cable trying to drag it and their other truck had engine problems. Appreciate the reply. 

Did you try the battery disconnect? I thought I read somewhere it didn't work for some. ✌️

Posted

Yea, sorry for the no reply.  Yes I did the ol battery and computer drain trick. It did work last week but dealer was closed. I started it and turned it off 5 times like nothing was wrong.  Went to work on a call out and came home and nothing...remote start seems to be intermittently working as well. From everything i have seen it seems like its going to be door switch or BCM. I do get parasitic power draw. Dead battery overnight and have seen the screens staying on for a few mins longer after shutting the door. The warranty company requires you have a gos tracker and its tied i to the BCM Via being pgysically connected to the OBD port so im thinking that may be an issue. GM covered themselves by adding in the manual "adding any other electronics may cause truck to malfunction" or something along those lines. I was able to get the Xtool D7 scanner(bi-directional) and get the parking brake off. So we got it towed without any issues on Friday evening to our local GM dealer. Hopefully this warranty company does get stupid and just pays what they should to get me fixed and running. I was explaining my problem to the woman taking my keys and such at Dealer and she said you can't program just 1 remote. 1 remote is all the truck came with. I told her that needs to be in the manual if that's the case because I read the manual and it says nothing about having to have more than 1 remote. I will come back and update once I get some input.   

  • Like 1
  • 2 weeks later...
Posted

the dealership has been great. they replaced the BCM and i had them do the 50k mile service even though this problem has plagued me for over 2 years and before the warranty ran out. I finally got everything reprogrammed and i thought i have my beloved truck back. then tonight it did it again. i didnt even remote start it but i got the remote learn pending with no control or power other than the door locks. i cant believe they cant find the problemto all of our trucks. ive had it. i fear it is time to explore my options. out of respect for everone on here i will not say what i want to say. you can probablyhear me screaming. at 65 i thought i had found my vehicle but a truck must not be for me. %#^&##%%!!!

Posted

I'm sorry everybody, but this had been a known issue for a few years now. My problem started over 2 years ago while I was still under the original warranty. Everyone out of warranty shouldn't have to be paying for this problem. Yet they still do not have a fix. I have been a good guy about this for a long time but that is starting to change. They tell me they have a fix, I get that good feeling about my truck (which I loved) again, and then WHAM. Remote Learn Pending. If it is only a few trucks that this affects, then make it right. I can't afford to trade this truck off, and I never want to. Nor would I do this to someone else. I someone knows about any legal actions I am finally open to them. I'm also extremely frustrated. I've owned the truck from new and have really only gotten to use it sparingly in the last year and a half or more. And why does this happen when you have to be somewhere quick or you are 1,000 miles from home? Tip: if you need to get someone to the hospital in an emergency, call an ambulance. Don't depend on GMC.

  • 2 weeks later...
Posted

2021 Sierra 1500 AT4. 

For what it's worth, for when those of you that become stranded. This also has happened to me on numerous occasions.

I have sort of found a " cheat code " during the inconvenient moment so that i am not left stranded during those times.

 

Instead of waiting the 30 minutes to try and reprogram the key,

 

Push and HOLD the start button for 12 seconds, then hit the lock and unlock button on the fob (separately). After this, the truck should no longer be in the relearn mode and should start like normal. (Brake pedal + start button.)

 

This does not solve the root cause. It should get you on your way until you are able to determine the fix. 

 

 

TL;DR

If push button does nothing,

- Press and Hold start button for 12 seconds, then release.

- Press the KEYFOB Lock button one time then the unlock button one time.  

- Then press brake and push button like normal. 

 

I hope this helps others who have been and recently started having this issue and been searching the interwebs.

 

cheers.  

 

 

 

  • Thanks 1
Posted

Not sure the cause, intermittent problems suck that way. When it happens you may try disconnecting the battery cables, discharging capacitors, and hooking the battery back up. Should reset the computer, hopefully letting you get on your way in under an hour.

Posted

Tried that. Didn't work for me. I am excited about the start button press etc..

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