I searched the forums, and couldn't find a post describing this.


First the truck.
I've got a 2002 Dodge Ram 2500 quad cab 4x4 with the 5.9 I-6 diesel.
No gauges connected to any of the illumination circuits. Stock radio. Aftermarket alarm attached to the parking light circuit.
The truck is mostly stock.

The problem.
Anytime I dim the dash light, I blow the under hood fuse for both the dash and parking lights. If I have the switch in the "parade" setting (the click just above the dimmer, but before the interior lights come on) everything is fine. parking lights on, and dash lights all work.

What I have tried.
I pulled the 5 amp fuse that runs all the dash lights. Still the outside fuse pops.
Replaced switch. still has the problem.
I check the wire(tan on back of light switch) to ground, no short.
while not necessary because I pulled the fuse feeding everything, it still pops fuses with the instrument cluster removed, ashtray light, and cup holder.

Weird note. after removing the radio, the fuse wouldn't pop. plug radio back in, and still wont pop. It did get dark by this point, and that affects how the VFDs light up in the radio, overhead console and instrument cluster. Don't know if it's related.

Any ideas??? I'm at my wits end here. I will check again tomorrow after the sun has risen to see if the fuse starts popping again.

 

i'd run a new fused wire to the radio. it sound like it might be on the circuit that's popping. radio likely has 2 wires, a low draw constant to hold memory and a main power wire that you could make switched to the ignition, or constant. your choice.

 

If you run the high draw (main power) to a constant, the radio will run when the truck is powered off, don't do that. Use a swtiched ignition source.

You could use the power button on the radio to kill it, but I'd be afraid of forgetting one time and walking out to a dead battery.

 

Don't think it has to do with the radio power. That pulls from a completely different fuse. According to the schematic, the fuse that pops only powers the parking lights and dash lights.

There is a light sensor that is supposed to control the VFDs. Anyone know where that is?

 

Well no luck on finding a solution. The dimmer is working just fine. I will update if it pops the fuse again.