Troubleshooting Trailer Lights Running After the Vehicle is Turned Off
Updated 03/28/2024 | Published 03/23/2024
Question:
I recently installed a wiring harness kit and the prodigy p3 brake controller on my 2016 Mercedes Metris. Everything seems to work fine except when I turn my vehicle off after a few minutes the trailer lights come on. I tested the 4 way connector with my circuit tester and was getting current at the brown wire. How do I resolve this?
asked by: Kris K
Expert Reply:
It sounds like something isn't wired correctly or the 4-way connector is bad but you've ruled out the trailer as the source of the problem. You will want to check to make sure that the brown wire is properly connected to the running light wire at the rear of your Metris and that the white ground wire is attached to a bare metal surface that is free of dirt and corrosion.
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Kris K.
3/24/2024
Thanks. Does the fact that the lights work properly other than the issue I’m having mean there is a proper ground connection and that it’s most likely the brown wire causing the issue? Would the lights work properly at all if it wasn’t grounded well enough?