Ford Truck Sending Error Codes for Trailer Lighting

Question:

ford smart trailer errors on screen saying right bulb is out, trailer disconnected. but the lights still work even when flashing fast. its a tow truck and as the 4-pin round poll connector and plug, right be side that is a a RV 7-pin round connector and works with no error. what could be wrong? the string lights only have right and left and brake-lights 3 wires white ,yellow and green it does work but get errors from ford smart trailer on dash screen.

asked by: Robert

Expert Reply:

I suspect your trailer string lights use high-efficiency LEDs that are confusing the bulb out sensor in your Ford truck. Because LEDs use so little power to illuminate it can appear to these vehicle systems that there is no power being drawn by the lights and this triggers the sensor to send an error message.

If so, you might try load resistors like # DI34ZR to see if that stops the messages. These will absorb some power and make it appear to the truck that a standard "power-hungry" incandescent bulb is connected. Often this corrects the error codes.

expert reply by: Adam R