Does the cluster backlighting go ON and OFF with the jumper in/out of the dimmer connector?

 

yes, exactly like that

 

Your bulbs seem good but your wiring seems faulty.

All can say for certain is, from the factory the Instrument Cluster backlighting is in parallel with the Shift Indicator lamp. Whatever one does, the other will do. For them to be out of "sync" someone would have had to modify the wiring.

 

Does it have something to do with not having the original stereo?

 

I wouldn't think so. I can't imagine a scenerio where the radio could differentiate between the Instrument Cluster and the Shift Indicator lamp. Reexamine the schematic in post #13. Every component in the backlighting circuit is in parallel. Whatever one does they should all do. Examine the status of each component (lit or unlit) with the jumper wire in the dimmer connector. If they are all lit except for the Instrument Cluster, the problem is in the Instrument Cluster wiring. If it were my car, I would print out the schematic and mark each component lit or unlit to see if a pattern emerges.

 

Doing tests I just realized that removing the jumper that is on the dimmer, the backlight bulbs of the instrument panel do stay on but with a very low intensity that seems to be off and the cockpit lights increase the intensity, putting the jumper raises the intensity of the instrument panel backlight bulbs and lowers the intensity of the cockpit lights to such a level that it seems that they are off

 

I removed the connector from my dimmer control this morning. None of the backlighting would illuminate.


For any of your backlighting to illuminate with the dimmer module unplugged you would have to be getting an alternate ground from some place. My next step would be to unplug that aftermarket radio and see what happens.

 

Should there be a negative on pin 3 of the dimmer?

 

Pin-4 (black) is ground. Puttng a jumper between 3 and 4 (for testing) will ground all the backlighting.

 

when i do that test the fuse blows