spayne460

I have checked these grounds. The problem is not intermittent enough to be grounds. It's pretty predictable. But yes body grounds to the frame and the one under the speaker. I could see if it was you hit a bump and it would start/stop but this is pretty consistent. I had some codes for the front view camera so I replaced it too. One piece of info I forgot to add is that I had a power tap to the mirror for a radar detector. I think that messed up the front camera and might have started all this. My next step is the HVAC module behind the glove box.

Long story short. 2016 GMC Sierra SLT 4X4 Z71 crew cab. When driving at night everything is normal. Lights work fine and instrument cluster is normal. After 5 to 10 minutes the headlights turn off, fog lights stay on and the instrument cluster goes to full brightness. The dimmer switch will control the HVAC and other interior lights normally, the cluster stays full bright and tbh I think it's much brighter than normal. The headlights will turn on with the manual headlight switch but the cluster stays full bright. After 5-10 minutes the cluster will go back to normal and the auto headlights work normally. This cycles randomly and only happens at night. I pulled the test procedure and tested out the light sensor on the dash. It tested good, but I replaced it anyway 3 times with dealer parts. I replaced the BCM, I replaced the instrument cluster. The only thing that is next is the hvac module that the light sensor runs through. I can program the modules and they are relatively cheap on rock auto so throwing parts isn't that much of an issue for me, but I am getting tired of dealing with this. Has anyone ran across this and found a fix?