Instrument cluster lights. Bulbs or wiring?

[justinae]

Working through the list of fixes for my 96 XLT 2wd. This one is the lights on the cluster. Naturally it's not staightforward.

There were multiple different plastic connector types which is suspect, but multimeter says bulbs and logic board have continuity. The lights on the stereo light up and do in fact dim when I rotate the wheel.

I plan to get new bulbs just because but I want to find the reason they aren't working.

I'd like to test the wiring going to the cluster to see if that's working right. Not sure where to start. I'll try to find a diagram of the constant power but is there anyone who's tested the harness before?

Are there are relays or other stuff I should start with?

thanks!

 

[justinae]

I'm a bit over my pay grade on wiring here but I tested the 12 pin connector for constant power. With keys in RUN position and headlights OFF I get 12.1v (neg on B/W pin 11 and pos on R/Y pin 5). When I turn headlights on the voltage drops to 11.9. Rotating the dimmer wheel doesn't change it.

Also took out by GEM to inspect and everything looked fine.

I remembered that my horn doesn't work either. Connected?