Brake Light on Trailer Not Working with 4-Way Connector

Question:

4 flat from vehicle to y harness, no lights until I hook yellow with ground wire at trailer light. These are LED. LIGHTS. I have signal and running lights but no brake light. When I push brake pedal lights go out. I have 4 flat tester that indicates that power from vehicle is working correctly. I have also ground all grounding spots to bare metal. Driver side connection brown w/ brown, yellow with yellow and ground connected to light stud. Passenger side green w/ green, green brown w/green brown.

asked by: Doug

Expert Reply:

Is the brake signal working on your tow vehicle 4-Way correctly? If you hardwired the connector on your vehicle side, then it could be that your vehicle has separate turn and brake circuits. Typically, these are both on the same circuit, but this can sometimes not be the case.

The only other thing that comes to mind is maybe the stop wire for your trailer lights is not connected properly or the bulb is out for that function. But that wouldn't explain all of the stop light functions not working at the same time.

Use a circuit tester like part # PTW2993 to make sure that your 4-Way sends the signal as you see indicated in the attached photo and we can troubleshoot further from there.

expert reply by: Jon G