I've had several GM rides with the auto dim feature, some had the issue , some did not!
I have replaced the light sensor at the little green bubble in the middle of the dash and dim switch still had the same problem on my '07 LS

 

I just read 4-12 and 4-13. This does not apply to the dimness of the LED's at times.
OldBlue say's he too has had a situation like what I'm talking about.
LED's go dim for no reason.

 

The reason is that the sensor thinks it senses a change in the ambient light.

 

I agree Don, that is why I tried to fix it but it wasn't broke! Different parts but the same issue! And so Namste! Breathe! And live with it!

 

Hello again,

Thank you for getting back to me. I'm sorry to hear that the automatic lighting is not what is causing this.

Have you considered taking it to your dealership? My team and I are not technical advisers, as we rely on our GM Certified dealerships to diagnose vehicle concerns. We'd be happy to schedule an appointment if that's an avenue you'd like to pursue.

If so, please PM us with your VIN, current mileage, full contact information, and preferred dealership so that we may assist.

All the best,

Amanda K.
Chevrolet Customer Care

 

Good call Whopper.
It might be or the switch is a poor design. Just went out to go to the store, sun in my face, LED's dim. Switch was in the full brightness position. Moved it up and down (not left to right) and LED's got bright.
Now to explain this to the dealer being I still have full warranty. You know the story. "Can't find the problem, everything is working fine. Bring it in when the problem happen's"

 

Amanda K I have sent you a PM.

 

No big deal - just move it back and forth from (dim to full) several times to clean the internal contacts. A shot of contact cleaner might be in order if it still acts flakey

Unless you have sort of super-duper warranty that you paid extra for, I doubt that the dealer will cover it, being your hhr is a 2010 vintage.

 

I just bought the SS a few months ago that is pre-owned certified from a Chevy dealer. It has a full 2 year warranty on it.

 

Sounds to me like something goofy is happening..

FWIW, sliding the dial to adjust brightness, won't do anything (at least in my 08) without the actual headlights being on, and not just the running lights...