No Instrument or Ambient Interior Lights

Trying to sort the last major issue on my new-to-me, cheap 1997 Riviera.

As the title says, I have no instrument or ambient interior lighting anymore. It was all working when I first got the car, but after having the drivers door panel off to install a new exterior door handle, they all quit. The digital odometer, climate control and radio all still dim when the headlights are on, but all lights associated with the dimmer don’t function. It could just be a coincidence, but I also lost the function of the traction control button at the same time.

I did check all the fuses and pulled the headlight switch apart to clean all of the contacts. All seems fine there. I even pulled the door panel back off to make sure no wires were pinched and shorting out.

What should I check next? It’s stumping me.

I've replaced two headlight switches this year (not on the Riviera). They do die.

True, but all other functions of the headlight switch still work and I’m getting power to the instrument light fuse with the headlights on. Is there another component of the dimmer?

If you did not disconnect the battery before doing the door work, you may have accidentally shorted something and blown a fuse.

Check the fuses, and check the connector that plugs into the drivers' armrest switch cluster, and the wire bundle that passes thru the doorjamb on the drivers' side (it's probably OK).

Albertj

No, I didn’t disconnect the battery. I’ve checked all 3 fuse boxes, all the fuses, and the wiring/connections in the door panel. Everything seems fine.

TypeRated wrote:

True, but all other functions of the headlight switch still work

It seems to me that the entire switch wouldn't fail at once. It didn't happen that way with my other two vehicles - some functions worked, some didn't.

I just had the same issue when I took apart the steering column to replace the ignition switch.  Meaning I also disconnected the headlights long flat green clip harness as well as the blue clip at the traction control.  In the daytime, the controls were bright, as indicated by the strong LED of the HVAC controls as well as the radio display.  However, at night, same dim appearance of everything mentioned above by Brad.  However, I did NOT have the headlight switch nor the blue, call it traction control/trip reset harness connected. Once I got everything put back together, life's good.  Wondering if it has something to do with the harness connecting the headlight switch.  Also, check to see that the rheostat isn't turned all the way down.  As me how I know about that little fashion faux pax.

Well, I finally found the issue. The dimmer on the headlight switch controls a rheostat that’s mounted under the dash on the steering column. The rheostat just happened to go bad. I temporarily bypassed it (a mini fuse works perfectly) and now have dash lights. They’re full bright, but certainly better than nothing.

I'm surprised the rheostat is separate from the light switch.

What would be super helpful would be if you could give an approximate location of this rheostat.  For instance, do you need to remove the clamshell surrounding the steering column, or have to remove the lower knee bolster to find it on the steering column.  This is a common junkyard part but available on RockAuto for $49 bucks.  There's an Aurora in the Vancouver, WA yard and I've noticed that my instrument panel, and my radio and HVAC units are all dim.  The headlight switch for my '98 Riv may be a culprit, but that switch is Riviera specific, '97-'99.  Just wish I knew where to look.  Here's a picture similar to Rock Autos.  These are common on a large variety of GM cars.

Problem SOLVED.  Call it the "bonehead of year" repair.  When I replaced the multifunction switch about 2 months ago, and putting everything back in place, I took the long green flat wire connector and place it ABOVE the receptacle full of male pins.  Another "D'oh" moment in my life.  Hooked the connection up to the back of the light switch and everything peachy keen.