HUD not working losing voltage.

[monty87]

So, first time posting, wish it was under better conditions, but my HUD quit working. pulled out my computer and got Fault Code -
B12AC-00 Loss of low voltage differential signaling to head-up display.
After a full afternoon of googling and searching everywhere I can think of I need help. Has anyone run across this? and how did you fix it?
truck is a 2020 GMC 2500 AT4 diesel.
I cleared the code and HUD worked for 5 mins and quit. tried clearing code again and did not come back on. I used to fix cars for a living but stopped about 10years ago. that being said I'm pretty stubborn about
taking my car to a dealership and have them fix it for me. Wanted to ask for help before starting to take it all apart. I have a feeling it's a poor connection somewhere, but I could be completely wrong.
thanks in advance!!

 

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[Ohiost90]

Could very well be a bad connection. I would start with the ground for that control module. good luck.

 

[monty87]

Stuck my head under the dash to look around. Best bet going to be taking everything apart to track wires down. BUT if I hit a bump in the road while driving the next time I turn my truck on it works again. Hit a bump and it might turn off. been on and off since I've posted. and recently it's been on for 2 days straight.

 

[btAT4]

So, first time posting, wish it was under better conditions, but my HUD quit working. pulled out my computer and got Fault Code -
B12AC-00 Loss of low voltage differential signaling to head-up display.
After a full afternoon of googling and searching everywhere I can think of I need help. Has anyone run across this? and how did you fix it?
truck is a 2020 GMC 2500 AT4 diesel.
I cleared the code and HUD worked for 5 mins and quit. tried clearing code again and did not come back on. I used to fix cars for a living but stopped about 10years ago. that being said I'm pretty stubborn about
taking my car to a dealership and have them fix it for me. Wanted to ask for help before starting to take it all apart. I have a feeling it's a poor connection somewhere, but I could be completely wrong.
thanks in advance!!

I am having the same HUD issue as you described on my 2021 GMC Sierra 1500 AT4. I checked all the IC fuses and they all looked fine. Did you end up fixing the problem and what was the solution?

 

[gemarsh]

I am having the same HUD issue as you described on my 2021 GMC Sierra 1500 AT4. I checked all the IC fuses and they all looked fine. Did you end up fixing the problem and what was the solution?

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