Diagnosis instructions for the trailer module

The trailer module (AHM) detects and reacts to the following faults:

• Checksum error of the various memories and watchdog reset
• Faults of the CAN drivers
• Line faults of the CAN interface and of the brake light input
• Line fault of all outputs with short circuit and wire break
• Undervoltage or overvoltage and implausibility of the voltage at the trailer module (AHM) compared to the vehicle voltage
• Implausibility of a CAN message "Braking" compared to the hard-wired brake light input at the control unit
• Implausibility of the sense values of the lighting outputs of the control unit
• Faults at the lamp outputs of the trailer module (AHM) are output as Check Control messages