The BCM outputs the illumination signal of each rear light to the trailer side via the trailer socket middle connector. Also, the BCM determines whether the trailer is connected or not based on the trailer detection signal input from the trailer side via the trailer socket middle connector. If the BCM receives an error signal from the trailer side via the feedback circuit when it detects that the trailer is connected, the DTC is set.
Condition for running the DTC
Condition for setting the DTC