strange electrical problem

[zoomsplatt]

hello group, I'm hoping somebody else's had this come up and can save me some time, all my lights work, high and low beam, breaks, turn signals, emergency flashers, backup lights, interior overhead light, cigarette lighter, all my gauges, and everything else except my running lights and my dash lights, started really funny, I'd turn my lights on and my dash lights would come on real slowly, like there was a rheostat connected to it that was being turned up a little at a time, this went on for about two weeks and then all of a sudden no dash lights or running lights, I've checked my fusible links, my fuses, my relays and I just put in a new multi-switch and alternator that I bought from Al but this all happened about 10 days after I did that, there's got to be a short somewhere but I don't even know where to begin to look any suggestions would be appreciated, by the way this truck does not have a dash light dimmer switch, never had one. it's a 1982 King cab diesel of course .
Thanks in advance: zoomsplatt

[asavage]

Take a look at 1982 720 FSM EL-59.

With the MF switch ON, check for power at Fuse 13 (both sides), easy enough. If you've got power there, you can discount the fusible link. Then check for power going into the MF switch (again, with the switch ON) at connector 76M wire Red/Green, and coming out of the MF Switch at wire Red/Yellow.

Those are the easy ones to check.

[zoomsplatt]

thanks for the tip Al but it was a resistance short in the drivers side rear tail light, the original owner had stuck a pair of aftermarket brake and running lights up on the truck box, sort of where the more modern trucks have theirs, he did a real lousy job of putting them in,(wires ran on the outside of the lights and just hanging down the side of the truck bed, used wire nuts instead of butt end connectors and electrical tape he also cut the wires away from the old lights and only left a 2 inch wire stubs)he brought the wires out of the aftermarket lights out the side of the lights instead of drilling a hole and putting them inside the panels, then just put four screws into the light frame causing the frame to come down on the wires, over a short period of time the pressure and vibration eventually worked its way through the insulation on the wire and slowly shorted it out, now here's the interesting part, it didn't short out all the way, more like he put a resistor in the line and over a period of time the resistance slowly went up but not high enough to blow the fuse but it did cause the contact in the multi-switch on my column to heat up, heating it up enough to melt the little pushpin that picks it up when you rotate the light switch so I had to replace a whole light switch assembly that I just got from AL a few weeks ago, anyway replaced the wiring into the lights and everything was/is fine. glad that's over, as soon as I get a chance I'm going to replace the whole truck bed with a more recent one and go with the new style lights.
Thanks again