Fuse boxes are only getting partial power?

KARL Z

MEMBER
1997 GMC C1500
5.7L
V8
4WD
AUTOMATIC
200,000 MILES

I just changed out the starter relay, and the ignition relay, now only getting partial power to my fuse box under the hood, I also found an unplugged red wire (mystery wire) and no power to the cab fuse box and an unmounted blue wire going from the fuse box to under the dash to be plugged into nothing.

1 Reply

KEN L

MASTER CERTIFIED MECHANIC
48,380 POSTS

This sounds like you have an ignition switch that is not working correctly or there is a maxi fuse that is blown. Here is a guide to help you check for power and the power distribution wiring diagrams that feature the ignition switch so you can confirm the failure.

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

If the fuses are good here is how to change out the ignition switch. Check out the images (below). Please let us know what you find. We are interested to see what it is.

Images (Click to make bigger)