1994 s-10 purchased used. Had a bad rear view mirror switch so I
replaced it. First time using the new switch, it too went bad.
I check the power and I am getting power from what appears to be 2
sources. This would be on the orange wire to the switch. I say this
because if I pull the fuse for the mirror switch, the continuity light
continues to light. If I also pull the courtesy light fuse the probe
light goes out.
After spending lots of time on this, I have also discovered that when
doors are closed the dome lamp glows, but it is dim. If I pull the dome
lamp bulb, the problem goes away, and each fuse acts correctly.
The truck does not have DRL, and I have replaced the mirror switch, the
third brake light, the door jamb switches, the headlight switch, and
the dimmer switch, with brand new GM parts.
I did pull the door panels, as well as the accordions from the doors to
the pillar and saw no cracked, broken or stripped wires. When I look
at the schematics, I don't see where these two circuits cross paths.
Assuming I want the dome lamp to work correctly, anyone out there have
any ideas where to look for the problem?
Thanks in advance!