Troubleshooting Signal Light Fuse that Keeps Blowing on 2004 Jeep Liberty

Published 09/26/2018

Products Featured in This Question

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

(80)

$71.46

Hook Probe Circuit Tester

(62)

$13.33

Question:

My signal light fuse keeps blowing #39. The fuse works for a few hours after being changed. Ive changed the fuse and even amped it up a few times. And still blows it out. Ive even changed the bulbs. And the multi function switch is still good, Ive bought a new one and still nothing. So I know thats not the problem.

asked by: Kayla9708

Expert Reply:

If the signal light fuse on your 2004 Jeep Liberty keeps blowing when hooked up to a trailer most likely there is a short somewhere on the trailer wiring.

First though I recommend testing the connector on your Liberty without the trailer attached with a circuit tester like # PTW2993. Just make sure you are only getting power at the appropriate pins when the corresponding function (turn signal, running lights, etc) is activated on the vehicle. If you are getting power when there should not be any then the issue is actually somewhere on the Jeep.

If the connector tests fine, then I recommend inspecting your trailer. Start with the connector and check for any debris or corrosion that might be built-up inside the pins. Sometimes corrosion can bridge two neighboring pins together and cause a short. Also check to make sure your main ground is securely attached to a clean, bare metal surface.

If all that looks good, then the next step is to simply inspect the wiring along the trailer for any exposed or damaged sections that need to be replaced.

If you still aren't able to resolve the issue, please let me know and we can continue to troubleshoot.

expert reply by: Chris R