Tesla Model Y Trailing Wiring Not Working Passenger Side

[Pushcart8209]

Problem: My 2020 Model Y is not illuminating the passenger side trailer lights. The driver side work fine. The passenger side car lights blink fast when in tow mode.

This used to work last year when I towed a trailer. I was in a fender bender (less than 10mph) earlier this year but it is cosmetic damage to the lower bumper and I can't get it into a body shop until next year.

Debugging steps:

- Swapped to another trailer, swapped 7 to 4 pin adapters- same issue of driver working passenger failing. Tow mode icon red.
- Tried using a 4 pin tester and 7 pin LED tester- neither illuminated. Tow mode icon red.
- Hotwired driver/passenger lights together- both illuminate on the trailer.

What can I try next? I have a service appointment but it is scheduled further out than I would like. So, I am happy to put in some elbow grease to try and fix this myself.

 

[bobkart]

So neither running lights nor blinker/brake lights turn on for the trailer right side? If yes, that's odd because those are two separate conductors according to this Wiki page:

Trailer connectors in North America - Wikipedia

en.wikipedia.org

Possibly the lower (rear?) bumper damage broke those two circuits. I've not had mine apart yet to see where the trailer connector is wired from, but it could be at the rear light fixtures.

A voltmeter could be used to confirm the theory that the appropriate trailer connector terminals on the car are not being energized when they should. Then it would just be a matter of removing parts until the wiring could be traced back to where it connects to the rest of the car. If that tracing leads back to the damaged parts, that could answer the question. Then possibly a temporary repair could be made (wire nuts?) until the body shop has a chance to do it right.

I see that this is your first post here, so Welcome to TMC! I'm in the PNW too by the way.