Troubleshooting Both Trailer Turn Signals Coming On Dimly with Turn Signal of 1999 Chevy Express Van

Published 10/09/2021

Products Featured in This Question

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

(155)

$75.03

Curt T-Connector Vehicle Wiring Harness for Factory Tow Package - 4-Pole Flat Trailer Connector

(25)

$12.20

Hook Probe Circuit Tester

(61)

$13.33

Question:

brake lights and running lights work on trailer but when turn signals are on either left or right both sides blink rather dimly at same time

asked by: Jeff B

Expert Reply:

That sounds like there is an issue with the ground wire or the connection between your trailer connector and the connectors on your 1999 Chevrolet Express Van.

If you have the factory tow package you should have a ground wire like what the Curt # C55240 has so I would start with making sure that is securely connected to clean, corrosion free metal.

Now if you do NOT have the factory tow package your harness will not have a ground wire that needs to connect to the frame of your vehicle so you will want to remove the harness and check both the trailer connectors and factory connectors for any bent pins or debris that is causing your issue.

If that all checks out then without the trailer connected use a circuit tester # PTW2993 to test the 4-way connector on your trailer and see if both left and right turn signals blink together or not. If they do not the check the ground connections on your trailer as one or more is not making good contact to the trailer.

I included a link to a helpful article on troubleshooting wiring for you to take a look at.

expert reply by: Samuel C