94 Formula
My 5 amp dimmer fuse, which controls all my dashlights keeps blowing.
The problem is it blows 15 mins. to 45 mins. after I replace it (while headlights are on). The fuse will last as long as my lights are off.
I replaced the dimmer swich/headlight switch control module (still happens).
Any ideas where else to look for this problem.
If it blew right away I'm sure I could find it, but it happens after a period of time.
No work was done, this came out of nowhere.

 

Anybody??????

 

What you need is a good diagram of the circuit and start isolating different parts of it untill you find it.

 

The fuse is after the dimmer, so that wouldn't be the problem.
These things are after the fuse(13)
Fog light switch lamp
Instrument cluster lamps
Radio illumination lamps(if stock)
SIR coil assembly
Steering wheel controls, radio
Ashtray lamp.
PRNDL illuminator(if auto)
HVAC control lamps
Both door illumination lamps

It blows while the(park) headlights are on because that's the only time it's in use.

 

I feel your pain man. Went through this about a year ago. I, like you went for the obvious things first. Turned out to be one of my taillight sockets was shorting out. Pull your taillights, remove the bulbs and thoroughly inspect the plastic sockets inside and out. Look for discoloration around the contacts or any corrosion on the contacts themselves or any disconnected wires. If anything is wrong with it just replace the socket. Like 5 bucks at your local parts store. Hope this helps, I know what a pain in the a$$ it is to drive with no guage cluster lights at night.Good luck and happy hunting!

 

Have you tapped into that wiring to power anything else? Sounds like you have an excess load on the circuit, either from a device you added or a high resistance ground.

 

Pay close attention to what you have on and what draws it power through that fuse. It sounds like it could be heat related. As certain electronic items start to heat up they can start to break down causing resistance to drop in turn causing current flow to go up.