Troubleshooting No Power From Converter Box on Reese Wiring Harness on 2002 Toyota Tundra

Updated 04/25/2023 | Published 04/24/2023

Question:

Im trying to fix a trailer wiring problem. The combo 7-pin and 4 flat connector was added by the trailer dealer in 2020 - worked fine until this week. Everything except the right turn signal is working. I have focused my efforts on the truck since my tester indicates it is a truck wiring problem. Ive tried doing continuity checks between the harness connector on the truck and the 7 pin. I cannot get continuity through the Reese Super Duty Circuit Protector. I dont know what is inside this connector and wonder if it is the problem. I cant tell if it can be opened and serviced. Thanks for your thoughts!

asked by: Mark A

Expert Reply:

Based on the steps you have already taken it sounds like the converter box is bad which means it will need to be replaced, not opened and serviced. The only thing I'm not sure about is what wiring you specifically have. From what I could find it doesn't look like there is a plug and play 7-way for the 2002 Tundra.

This leads me to believe that you have a 4-way wiring harness plugged into the factory port with a 7-way adapter added on. If that is the case, you only need to replace your 4-way using the # 118378. The 4-way connector should plug into your 7-way adapter and you'll be all set.

expert reply by: Robin H