So while I was driving with my lights on a couple of days ago I hear a slight click or pop and my gauge lights went out. Also my aftermarket stereo normally auto dims when I pull the headlight **** to turn on the headlights. It brightened back up and no longer dims when I turn on the headlights. My warning lights on the dash still light up and turn off on startup. The little digital odometer still works. Turning the headlight **** still turns on the cabin dome lights, but does not dim the instrument cluster (totally dark).

I went out today and swapped in a new fuse for the instrument cluster (10A on #7 as I recall) and no luck. I tried the fuses in other slots and they work.

Is this just a burnt out bulb? If so why won't my stereo dim?

Edit, some searching says maybe it's the headlight switch. Sure would be nice if people having the same problem as me would come back to confirm whether they were able to solve their issue or not.
https://www.ebay.com/itm/11553439773...mis&media=COPY

 

To update, I'm 99% certain that it is that headlight switch that I linked above. I went out and played with mine. If I get it at just the right angle and pressure my dash lights will come on. Like 1 out of 50 chance and you have to keep holding it just right.

 

It's called a rheostat, Remove the switch and have a look at it. If it's not burn try some electronics cleaner on it. It may just be dirty.

 

Well I replaced the part and my instrument cluster is still dark. Tail/running lights on my trailer also don't come on when I turn the headlights on. I know the IC lights work because holding the original switch in just the right position caused the IC to light up. Night driving without being able to see my speedometer is a problem.

 

Ok, it's more than just the instrument cluster. Also tail lights, license plate lights, and trail tail lights.

Mechanic tried to tell me that it's the switch. When told that I already replaced the switch he said he needs to order the switch. I really don't think it's the switch at this point.

 

For the rear lights, they all go to a common ground, including the license plate lamp. G305, it says "Right side of body"...... Yeah, ok. I am assuming that means passenger side, and it *should* be in the back somewhere....

 

Ok, I don't know anymore. Messed with fuses, no luck. Also realized that if I start to pull out the head light **** but stop it before it reaches that first click, everything works. Instrument cluster lights up, odometer dims, thermostat ***** light up, stereo dims, tail lights come on, amber headlights (fog lights?) turn on.

If I pull the **** far enough for the first click everything turns off. If I pull it to the second click the headlights come on but all of the above remains off.

So all of the hardware works, but for some reason neither headlight switch works so far.

 

Replace the switch, again..... it is NOT working properly.

 

I'm not the brightest bulb in the box, in fact I may actually be a moron, but even a stopped clock is right twice a day. My 1500 is currently parked about 10 feet in front of my parents' '98 3500, which currently has a working headlight switch and instrument cluster. You can probably see where I'm going with this.

Confirmed, the working headlight switch from the 3500 DOES NOT WORK in my 1500. Strongly suspecting that it is not the switch at this point. I should have thrown the two from my van into theirs to confirm they work, but whatever.

My next suspect is the wiring harness connector.

I don't suppose anyone has a diagram for that thing so I can try to bridge the connectors to test this theory?

I also just realized, the 3500's warning buzzer comes on when I turn on the headlights when it's not on, but mine doesn't.

 

Have a look here for wiring diagrams.