I replaced the headlight switch in the '81 the other day, and now the dome light stays on when I turn the headlights on. And no matter which way I turn the knob, it still won't turn off.  WTH?!

This problem didn't occur with the old switch. The reason I changed the switch, was the rheostat part of the switch was overheating and smoldering.

Any ideas?

When the switch is rotated in normal operation the dome light wires are grounded by the headlight switch.  I suspect something is grounding the wire.  It could be a defective switch.  Look at your old switch.  You will see when the very front of it is rotated, it pushes down a contact lever that just hits the switch housing.  The housing has a ground wire.  When they contact the circuit is complete.

Either this contact is stuck shut, the switch is shorting, or the wire has been pinched to ground.

OR some other weird off the wall crap just happened at the same time.  Not likely, but I have seen weird non-associated things.  But not likely.

Thanks Ken.

BTW, is it normal for the ceramic part on the switch to get hot while the lights are on?

Darryl 

Any areas within the lighting system in specific I should be checking out?

Darryl

Any over load on the dash light circuit.