Both Turn Signals Come on the Trailer When Only One is Used

Updated 07/24/2017 | Published 07/21/2017

Question:

When turning on the turn signal both sides flash. Have checked the wiring. Seems like power is being delivered to both sides via. the running light wire. Is this a possible ground issue or incorrect bulb. Thank you

asked by: Brant B

Expert Reply:

The wiring in your setup definitely has a short somewhere. Start off by checking the connectors on both your trailer and your tow vehicle. Look for any pins that are damaged or any parts that are corroded. Corrosion will look Green or White in color. If those look good then check your grounds. Make sure they are all connected securely and to a bare metal surface.

If that doesn't fix it then you will want to test the connectors on both your tow vehicle and trailer to see which one is the culprit. You can use a Circuit Tester # PTW2992 to test each function (or pin) on your vehicle and a 12V battery to test each function (or pin) on your trailer.

Once you have established which end of your towing setup is the problem then you will need to check the wiring on either your trailer or your tow vehicle, depending on what your results from testing are, and look for spots that have been bent, damaged, have exposed wiring, or are corroded and replace it accordingly.

If that does not fix your problem please let me know and I would happy to help you troubleshoot further.

expert reply by: Jon G