B1803 – Lamp Turn Signal Rear Output Circuit Open

B1803 Possible Symptoms

Engine Light ON (or Service Engine Soon Warning Light)

B1803 Possible Causes

Faulty Lamp Turn Signal Rear,Lamp Turn Signal Rear harness is open or shorted,Lamp Turn Signal Rear circuit poor electrical connection,Faulty Body Control Module (BCM)

B1803 Description

The Body Control Module (BCM) monitors the Lamp Turn Signal Rear. The BCM sets the OBDII code when the Lamp Turn Signal Rear is not to factory specifications.