Troubleshooting Trailer Lights Not Getting Power On Vehicle Side

Question:

I have a 2008 Highlander that we had trailer lights hooked up. They worked for 3 years and now we are not getting any power to the OEM harness on the vehicle side. We have checked the fuses that the manual say go to the towing package and they are fine. Any other suggestions?

asked by: Susan S

Expert Reply:

From what you've shared it sounds like the issue is squarely on the vehicle side. If you've already ruled out a fuse being the cause, next I would use a circuit tester # PTW2993 at the plug where your harness connects to. Included is a video showing how to do this. If the functions are working as they should, you will need a new harness. The Curt T-Connector Vehicle Wiring Harness for Factory Tow Package # 56042 is a solid option to consider if you need.

If you identify the problem there during your testing and you've already ruled out the fuses and relays, you likely have a damaged wire on your Highlander and shop would be your next stop.

expert reply by: Patrick R