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Instrument Panel Light Dimmer Switch

3K views 4 replies 4 participants last post by  evintho 
#1 ·
All of a sudden, the instrument panel lights went out last night on my 1991 LX Hatchback. Fuse is fine, and the overhead light still works. I've seen carbon pitting on some of the all in one light switches (and have fixed them), so i removed this one. It has two steel coil style resistor wires wrapped around a plastic shaft. There is one on the top and bottom of a gear drive wheel, and there are two 'points' one on top and one on the bottom, each of which contact the resistors.

I proceeded to use a small cleaning wheel (Dremel) to clean up both the coil wires (weren't all that bad). The points i cleaned up with a small ignition file, and there were also two buttons, again one on top and the other on the bottom, that were at the 'end' of the travel where the overhead/dome light engaged. I cleaned up each button (one was copper colored the other more silver color) as well. Put some D5 Deoxit on the whole thing.

Now, I actually get dash/instrument panel lights full, but in a very very small area of travel, right next to where the overhead light engages. It's easy to get both overhead dome light AND the instrument panel lights on at same time, but getting just the instrument panel lights on without the dome light is tricky. You have to nudge the dial to the left ever so slightly away from the full right setting. But go a little too far and the instrument panel lights go out altogether. The 'fade out' no longer works.

Something is still wrong, obviously. Would anyone have any advice? There appears to be a small resistor inside the unit that you basically can't get to without tearing the thing apart (but i'm thinking about it!). Betting it is bad.

Has anyone rebuilt one of these fully?

Thanks,
Robert Tilton
 
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#3 ·
Don’t you mean the instrument panel dimmer switch is bad? The actual headlight switch on our cars is not a resistance switch but just a contact type switch.
 
#4 · (Edited)
The easiest fix would be to buy a new/reman one,but if you don't want to do that,the info in the next paragraph shows instructions on how to wire the dimmer switch wires so that the instrument cluster lights will come on full bright when the headlights are turned on,bypassing the dimmer switch for the cluster lights.The source of this info didn't list whether the dome light would work anymore.Youll have to check all of the wires connected to the dimmer switch to see whether removieng the blue/red and one of the brown wires will still allow the dome light to work.It should leave the dome light wires connected to the switch,but not the cluster lights.The dimmer should control the dome light while the headlight switch should control the cluster lights...



"On the back of the dimmer switch plug, find the Light Blue/Red wire (on one end of the plug), and the two brown wires that go into one of the oher terminals. Use a piece of your own wire about 4" long and the same or larger size, and a couple "tap" connectors to jump from either brown wire to the single Blue/Red wire.This bypasses the unreliable rheostat dimmer so the instrument lights come on full whenever you turn on the headlights"
 
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