Troubleshooting Trailer Wiring That Activates The Hazards When Using The Right Turn Signal

Question:

I have a travel trailer that I’m confounded by. When connected, with towing vehicle headlights on, everything works as it should on the trailer. With tow vehicle headlights off, the right turn signal triggers hazards on the travel trailer only but all other operations are as normal. I could just drive with headlights on at all times but that’s not fixing the issue. Any thoughts here?

asked by: Justin

Expert Reply:

Hey Justin,

When you say it's triggering the hazards what exactly do you mean? Is it flashing the smaller clearance lights on the trailer? Is it just on the right side or the whole trailer? Most likely the converter box for the trailer wiring harness on your Highlander is malfunctioning and sending the wrong signal back to the trailer. You can't do much to fix this unfortunately besides replacement if this is the case. If you have the factory towing package you can swap out the wiring with part # 118449. For models without the factory tow package you'll need the # C59236 instead.

expert reply by: Kevin C

Justin

6/14/2024

Thanks for the reply, Kevin! The right turn signal triggers hazards on all lights on the trailer including the smaller clearance lights. Thanks for the information. I'll be looking into replacing the converter box.