1996 GMC Yukon Failed courtesy lights, exterior mirror cont

BURNETTW

MEMBER
1996 GMC YUKON
V8
4WD
AUTOMATIC
112,600 MILES

1996 Yukon SLT, 5.7L, 4WD, 112,600mi. No Courtesy Lights. No exterior mirror control. No Daytime Running Lights(DRL). All other lights, dash lights, pwr seats/door locks/windows, radio, and RKE work fine.

Fuse #3(20 amp), in drivers side panel, will blow immediately when replaced. All other fuses appear to be good. Voltage on fuse #3 slot checks at 12.52 and about 38 amps.

There was no warning or intermittent failure prior to complete failure. I suspect the DRL system but not sure what to do about it. Is the DRL control under the dash? Can it be unplugged? There doesn’t seem to be much info on this kind of problem.

Thank you.

2 Replies

FLEXY5

MECHANIC
512 POSTS

If it blows immediately, my first inclination would be to look for a short somewhere. I would start unplugging anything that fuse feeds. You can also go to your local parts store and get a 10 or 15 amp breaker to use for testing. You may need to make some leads that will insert into the fuse box. This way you don't have to constantly go through fuses. But it sure sounds like you have a dead short somewhere. If you unplug everything and it still does it, start checking wire harnesses. A common failure point is the drivers door where the wires go through. Check this stuff and post back.
Dave