After studying the FSM, it seems this device, whatever and wherever it is, provides lighting to a number of areas, none of which work in my 1991 coupe. All fuses and relays and wiring have been double checked and seem OK.

It seems that there should be lighting in the DIC, radio head, HVAC control, shift indicator, power windows, power seat, and other areas -- none of these areas (and possibly others) have any lighting in my vehicle regardless of the light switch position. Are these all supposed to have light?

Does anyone have any experience or suggestions on what this device is, where it is located, what it looks like, and, most importantly, if it is bad would it cause the problems I am experiencing with my interior lights?

Thanks again to all your experts!

Is that a fancy word for "dimmer switch"?

http://www.rockauto.com/dbphp/prt,301,D1509B

That sure looks like the same as the diagram in the electrical manual...do you think if it was bad it could cause the problems I posted with the illumination? According to the manual it feeds all of those bulbs...any idea where it is besides "under the dash"?? Thanks!!

Joe

Can't help you there. Usually on the page after the wiring diagram, the FSM shows a list of all components in the diagram and refers to a figure that shows a sketch of where it goes.

It seems to be down around the bottom of the steering column; I don't remember seeing it when I had it all apart not long ago but then again I wasn't looking for this...anyone ever changed this part out (it's really a "dimmer")? Thanks!!

The "dimmer" is on the light switch. If it fails, weird things can and do happen.

The head light dimmer (high beams) is on the column.

Thanks...

I've had the steering column apart, so I know very well the location of those components (including the high beam dimmer switch).

I know the speedo display (which is "naturally" lit) dimmer is the knob around the headlight switch...this "dimmer" is supposedly down in the left hand footwell...

Nothing like reviving an old topic. I was connecting my new (to me) rear-view mirror and when I turned the parking lights on..... no interior lights (ex. instruments and courtesy). I perused my (also new to me FSM) and there it was... this "incandescent power driver" thingy. Never heard of such a thing. I located it, ran the tests and it appears to be the problem. To my amazement, this part seems to be available everywhere and is less than $40. I can sleep now!