Reverse lights and backup camera stay on while driving.

[mrbala]

I have a 2020 Yukon XL and my backup camera and reverse lights do not shut off when vehicle is in drive.

I see that this was discussed previously in another thread but with no resolution.

My reverse lights remain on while the truck is in drive. The normal display screen comes on when the key is turned to accessory mode but once the ignition is turned the backup camera comes on.
@Doubeleive says "it's either a shift cable adjustment or shift interlock solenoid...
you could start with a visual inspection of the shift linkage (under the truck) and see if it looks worn or has a piece of the sleeve cracked or missing"

Further research indicates a faulty relay may be the cause or the problem could be the reverse light switch (on the transmission).

The Problem Started during the current cold snap. I wonder if it is related.

Does anyone know which relay I should check?

How difficult is it to replace the shift interlock solenoid or reverse light switch?

 

[Doubeleive]

if you have a decent scanner it might show the relevant data and point to the cause.
that typically requires a higher end bi-directional scanner

 

[mrbala]

The issue fixed itself.
I didn't get to scan the computer.
Over the winter the screen would flicker intermittently. Flicker would properly show the screen but only for a micro second. This gave me hope for a simple fix. Hitting a bump did not seem to cause flicker. Just happened randomly.
The weather has been getting warmer However, it is still around the freezing point much of the time.
Last week while I was in for an oil change, we disconnected the wiring harness connection at the transmission.
There was no sign of corrosion. We sprayed it with MAF cleaner and applied dielectric grease and reconnected the harness.
The issue was not fixed. However, shortly thereafter the screen started to flicker quite a bit. As I waited at the stoplight voila... the issue was resolved and has not returned.

Except... I notice that the screen turns blue briefly when going from reverse to drive. Not so going from reverse to park.

If you or anyone you know has any feedback on this issue please reply to this tread.

I am curious about the cause in case it happens again. Other members could benefit in future.

 

[mrbala]

Does anyone know how to check for GMC service bulletin for this issue?