Park/dash light fuse blowing

[FarmerDale]

I'm looking for a little help in diagnosing the problem on my 95 K3500. 2x in the last 5 months the parking/dash/clearance lights don't light up, and the fuse is blown. The first time I traced it to the tailgate lights, which clearly had a short. Last night I got to drive home w/o taillights or dash lights for the same reason.

BTW, I have installed a relay for the cab clearance lights and trailer lights to take the load off the light switch.

[HowieE]

If you do not find another short external to the switch take the switch out. While removing the switch check the connector that connects to the switch. Look at the orange wire in the corner of the connector and it's pin inside the connector. This is the weak point in the switch assembly and any overload, your old short, may have caused this connection to melt into the plastic. If this is OK remove the connector from the switch and check across pin H, the orange wire, pin E, the dark green wire on the switch. This is the reostat that controls the instruments lights. You should be able to change the resistance at these points by moving the reostat.If you find a problem there disassemble the switch. It looks hard but isn't that bad.
You will find a dogbone roller that travel across the surface of a printed circuit board that gives the light range of the dimmer. If it show any sign of burning or discoloration polish the edges of the dogbones were they contact the board and clean the other contact surfaces. Reassemble the switch and check across H & E again.

[jjgmc96]

i had a fuse like that blow that was giving me fits. i finally removed the adapter kit for a 4-wire flat trailer plug that plugs in between the taillight connectors and i didn't blow any more fuses.

[spra01]

Do the clearence light wires run to the back of the cab first?, if so there are wires run under the carpet by the drivers left foot that are prone to shorts.