Dash Lights Dimmer Switch

I have no dash lights but I have power to the dimmer switch. I have to play with the switch to get the dome light to work. I read on another post here about jumping the tan wire to another terminal on the switch to see if the dash lights come on so I can condem the switch. What am I jumping to do this test ?

It could be that the switch just needs to be cleaned. I was having trouble with my dash being very dark. I took the switch out and cleaned up the contact points on the adjusting wheel. It made a big difference in the brightness range of the dash.

Take a look at the wring diagram. The tan wire goes back to the fuse block. That's power to the switch.

Now follow the other wires on the diagram until you figure out what wire goes to the dash light. That's the wire to jumper to.

Looking at the Instrument Panel diagram again......... The Dimmer switch gets its power from E1-18T right from the fuse box.
M2-18Y goes to the Dome light and M2A-18Y goes to the right door switch. L7A-18BK goes to the Headlamp switch. Not sure where L6-18Y is going (see accessory wiring diagram it says).

Tracing back from the 4 cluster lamps E2A-18O feeds back to splice E2D-18O. E2D-18O goes right back to the Fuse Box. This appears to be the ground right ?

The following items are working.....The doom light will turn on from the dimmer switch if you play with it and the dome will light when the doors open. Headlight switch and headlights are working and the rest of the lights on the cluster work.

I am still unclear what to jump E1-18T to M2-18Y(Dome Feed) ? I would like to try working at the switch before I try and mess with the blubs. I am hoping that the issue is in the switch but I want to make sure before I spend the money on a switch.... My theory is that the rheostat is not letting enough power out to light the dash but is able to light the dome light.


Thanks again

clean your dimmer switch,dont jump it!look at the fuse that it takes/you will burn the spring on your dimmer switch and you will have to replace it!

I not very good at explaining things but, I'll try. You really have to pull that dimmer switch to test it. Granted you could just unplug the connectors to it and test it in place but, a real pain. Hey it probably has to be cleaned anyway. Dome switch jiggling tells me that. O.K. get a cheap ohmmeter (harbor freight has them free with any purchase right now). The dimmer is a variable wire wound resistor with a switch. When the dimmer is rotated to the (click) switch position, the middle contact should show a short between both the other contacts (or very low resistance 1 to 2 ohms). When un-clicked, the middle contact should show a open between it and one of the outside contacts but, it should show a short between it and the other contact. Leave the ohmmeter connected between the middle contact and the one showing the short and rotate the knob. The resistance should start to increase (which would dim the panel lights). I'm guessing that you will not see a short between these two contacts or a resistance change. That means that the wire wound resistor is really dirty or it has opened up. Granted this is assuming that your connections are all sound to the switch and fuse box. Let alone the instrument panel. (round plug on the back and maybe a bad circuit trace, also grounds). If you see the resistance jumping around between middle and the one that should change, take Roadcuda's advice and clean it good. Radio shack now sells DeoxIT. Great stuff but, pricey Catalog #: 64-249. Yes you could jumper from middle to top (dome light) then middle to bottom (panel lights) (with the headlights turned on) for a test but, I don't like the jiggling to light the dome. Switch is dirty. You could also leave it plugged in and short middle to bottom (tan to yellow/with tracer) and light your panel lights at full brightness and live with the dirty dome switch. Once again this is assuming everything else is sound. Sorry this is so long, just trying to help and I can't sleep.

I kept playing with the switch and got the dash to light. I ran out of time yesterday trying to get the glass out of the reverse light to change the blub. It was really stuck in there. Also ended up having to clean up the socket trying to get it to light up. Next week I will take out the dimmer and clean it. When the dash finally did light it looks like I have a few blubs out. The manual says that there are 4 blubs. Do you have to pull the cluster to change the blubs or can you get them from under the dash ? Thanks again to all for the great info so far.

You should be able to get the light sockets out from under the dash. They are a very simple quarter or half turn twist to loosen.

If you have to do a lot of work under the dash, pull the seat out.... It's much easier.