99 379 blowing acc fuse

you can ck. all clamps holding wiring harness down along from firewall to fuse box to dash panel,

 

Just a thought, Pull the left panel on your dash, should have inside of it a large relay. More than likely round. Check it out and make sure none of the wires are making contact with anything else. Turn your key on when investigating it and see if anything arc's. Might be as simple as that.... Good place to start, I know for a fact that thing will fry fuses....

 

What switch are you turning on that makes it blow?

 

My '94 was doing the same thing. It ended up being the backup light switch on top of the transmission Power wire 242 broke off and was shorting out on the transmission. For those wondering 94 379 does not even have reverse backup lights.

 

I was wondering if you have figured out the problem with blown acc/sw fuse. my 98 is doing the same thing mine blow's scond from top on switched power side of Panel .i thought maybe you could help me

 

2nd one down on right side is accessory switched, it is circuit #'s 242 and 304.

Do you have any accessories that were added to that circuit, 304 which is the left leg of that fuse powers every left leg on that side of the fuse box. 242 would run to whatever acc. is using it.

The wires are white and have the circuit numbers printed all along the insulation.

Read the post just before yours and that is the answer to what was wrong with mc8541ss harness.