How often does it happen?
How long does it happen for?
Was it replicated by the technician, and long enough for them to test it while it was not working?
Did they consult the Technical Assistance Center (TAC)?
Has it been looked at by a GM Field Service Engineer (FSE)?

I don't know what your truck needs, but it sounds like the dealer is trying their best to get you fixed, but they may not be completely out of resources yet.

 

How often does it happen?
How long does it happen for?
Was it replicated by the technician, and long enough for them to test it while it was not working?
Did they consult the Technical Assistance Center (TAC)?
Has it been looked at by a GM Field Service Engineer (FSE)?

I don't know what your truck needs, but it sounds like the dealer is trying their best to get you fixed, but they may not be completely out of resources yet.

It happens randomly. I thought they had fixed it, but no. It happens at startup. It either works or it doesn't for no rhyme or reason. For example I'll start it up and drive to Menard's it doesn't work. I come out of Menard's start the truck and it works. It doesn't flicker and go out. It works for a start cycle or it doesn't.

 

Yup, same thing - HUD mignt work/not work on any given day/start up. It's been at the dealer a few times, with no luck. They had opened up a ticket with GM TAC, and even they did not have a clue (per the dealer). Dealer now has a replacement HUD display on order, so will see . . .

34S

 

I noticed that my HUD has a couple of time gone dark. I think it goes dark when your low fuel level light comes on.
I noticed that after I refill the fuel tank it has always come back on. Not sure if it's a coincidence or if that's why the HUD goes dark.
Other than that, my 2023 AT4 has been flawless.

 

That sounds like a coincidence I'd mention to the dealer so they can look at the wiring schematic for a link.

 

Its a software bug afaik. It happens to me too, usually when the system boots up without the engine ever being turned on before it times out and goes into standby (think opening a door to grab something, getting out for gas...etc). Letting the BCM completely power cycle fixes it every single time for me, so I highly doubt its a hardware issue and more of a state management issue in the firmware/software.

 

Letting the BCM completely power cycle fixes it every single time for me

How do you accomplish that?

34S

 

The HUD on my '23 AT4 has started not showing randomly after I gotten the latest software update last week. Before the software update, the HUD always showed up. So, yeah, I do think it is a software bug.

 

My HUD does not work during the day cause I wear polarized sunglasses, at night it works great.

 

I thought mine went out due to the exact same issue. I busted up laughing when I realized I had my sunglasses on.…I realized what was up when I bent my head over and I could see it lit up again. Glad I’m not alone 😃

 

My husband is having the same problem & getting run around by dealer.