Dash lights
 

I have a 2003 Tahoe. Just yesterday, backing out of my garage, I noticed that all the instrument lights were off. At lunch they were back on. Same today. On the way to work, they came on. It seems like when the headlights are on, the instrument lights are out. Has anyone seen the same issue?:confused:

Welcome to the forum.:) Are you sure you didn't dim the illumination all the way down?

Dash lights
 

They are automatic headlights so they are untouched for the most part. Even the DIC display is dark which it would not be with the lights dimmed. Once the headlights turn themselves off, the dash lights come on without anything being touched.

The reason I was asking was, the illumination dimming function gets overridden during the day.

Thanks. If I cover the sun sensor on the dash, when the headlights come on, the dash lights go off. When I uncover it, the headlights go off and the dash lights come back on

Okay, that proves the ambient light sensor works. Now, can you confirm the illumination brightness setting on the thumbwheel next to the headlamp switch?

Might want to give the dimmer a few good turns to each extreme to reduce any oxidation build up on the dimmer, sometimes just sitting there at one setting can cause poor conductance after a while and moving the contacts around can do some self cleaning...

Did The Trick
 

Seems to have worked. Thanks Jeff.

I have this same problem with my 2002 Tahoe. If the headlights are on, the dash lights go out, except for if I turn the dimmer switch all the way up to turn on the interior dome light...then the dash lights come on. As soon as I turn off the interior dome light, the dash lights go out again. What should I try????

. If the headlights are on, the dash light are off
 

i have the same issue on a 2002 subk1500 wondering if you ever found the problem or solution other than removing the dome light bulbs