1A5X - 5

Condition







Diagnostic trouble codes (DTCs) are stored if the central electronic module (CEM) registers that communication with the climate control module (CCM) is not operating.

NOTE: In the event of CEM-1A5X diagnostic trouble codes (DTCs), the central electronic module (CEM) must not be replaced as the diagnostic trouble code (DTC) indicates a communication fault in the Control area network.

Substitute value

- None.

Possible source

- No power supply to climate control module (CCM).
- Open-circuit in the ground lead to the climate control module (CCM).
- Contact resistance in the terminals.
- Open-circuit in the wiring for the CAN low speed network to the climate control module (CCM).
- The climate control module (CCM) is not intended for this car (for example a used control module with different software/hardware).

NOTE: In the event of missing CAN communication, but with the power supply still on, the climate control module (CCM) will function for a few minutes after the key has been removed (Limp-home function).

Hint: If several diagnostic trouble codes (DTCs) are stored in the central electronic module (CEM) for communication faults with other control modules in the low speed network, this indicates a common fault in the Control area network, see the wiring diagram.

Fault symptom[s]

- The climate control system does not function.
- The lower row of buttons on the climate control system does not function.
- The climate control system functions after the key has been removed.