Hello everyone. Yesterday on my 2001 SS Monte the dash, steering wheel, radio, and heat/ac controls lights stopped working. After a few miles they came back. This happened 3 times yesterday The last time was a late night 70 mile ride home. They finally started working about 40 miles into the drive. The gauges, radio, cruise and temp. controls all worked as normal just not illuminated. I first suspected a loose wire to ground but there is no flicker on bumps, just finally start working then continue to work the rest of the drive. I noticed once that when they came on I thought I heard a sound like a relay click. The interior lights work fine.

Does anyone know where to check for a common ground for the dash lights? Are they on there own relay?

 

Hi Tommy.
First, to answer your questions, there is no separate relay for the instrument panel/HVAC/radio lamps. The circuit is grounded and controlled through the BCM, but there are 3 other points where the instrument panel is independently grounded to the firewall. Not sure which one is for lighting but they are under the dash, behind the IP, left, center and right of the brake pedal bracket. With that being said, I think your problem is in the dimmer circuit, either the headlamp/dimmer switch or a pin in the instrument panel harness connector under the dash near the DLC port. I lean toward the switch. You might try "fiddling" with the headlamp/dimmer switch the next time the lights go out. If that makes a difference it would suggest the problem is in the switch.

 

Thanks man! That gives me some places to check!

 

Update

 

Plumbob you were right. The problem was in the headlight/dimmer switch. After the last post the lights worked for a solid month or more, the finally the interior lights got wacky again. I ordered the new switch, installed it and problem solved. Thanks for the advice!

 

Glad It worked out Tommy, and you're welcome.

 

Not the least bit surprised. My first car had the same design light switch. It had a short, and if I left the interior lights turned up, it killed the battery. I learned to turn it down in the daytime, and problem solved.