[Gilochoa1]

I have a 1985 GMC 4x4 pickup.
My problem is that both rear running lights don't turn on when I pull the light switch. I can't drive it at night. The dash doesn't light up. and the dome light goes on very dim.
Head lights works, signal lights works front and rear, and so does brake lights.
But no running lights. Might it be the SWITCH it self that's gone bad??
I'm not electrical savvy. Any help would be very appreciated. Thank you.

[vicrod]

Before starting to find the problem make sure the bulbs are good. Replace non working bulbs with known good bulbs.
Check for good bulb contact and ground connections at the sockets.
The tail lights are on the same fuse (circuit) with the front and rear side marker lights and the license plate light. If these lights are all out check the tail light fuse.
The dash lights and, I think the dome light are on the headlight dimmer switch.
It is possible that a bad headlight switch is causing both problems.

vicrod

[EOD Guy]

Might be a bad ground at the dash and at the tail lights.

[snydski]

I've had a faulty trailer light whip cause that once but check the fuse first.