Troubleshooting Running Lights Not Working on a 2008 Chevrolet Silverado after Installing Wiring

Published 04/07/2011

Products Featured in This Question

T-One Vehicle Wiring Harness with 4-Pole Flat Trailer Connector

(459)

$33.95

Hook Probe Circuit Tester

(58)

$12.08

Question:

installed 118384 on 2008 silverado ext cab with tow package and factory 7 way plug. plugged to trailer 4 way, and brake and turn lights on trailer work, but not running lights. all trailer lights work properly when plugged to 4way on my other vehicle. is there some other wiring necessary?

asked by: Hentz M

Expert Reply:

I would start troubleshooting at the connector itself. Take the connection apart and make sure there are no bent pins or corroded terminals that could cause the tail light function not to work.

Next, I would check the fuse block under the hood of the truck. There should be a slot for a tow package fuse in there. Check the legend under the fuse block cover and you may find that this fuse is missing or that it has blown, and needs to be replaced.

Finally, check the connector at the rear of the vehicle again, with a circuit tester, item # PTW2993 if needed, this time. If the connector works with a test light and does not work when the trailer is plugged in there is likely a ground wire that is not making good contact. Check the trailer ground also to make sure that it is making good corrosion-free contact with a clean, metal surface.

expert reply by: Robert G