Checksum error on CAN-message CAF4 from ECA
Check the wiring and connectors on the TMS (E5) and the ECA (E93) Renew the ECA (E93), If the fault persists renew the TMS (E5).
What you'll see
No driver-visible symptom recorded.
System reaction
Amber gearbox warning. If vehicle is standing still, neutral position will be engaged. If driving, locked gear. Neutral position will be engaged when braking to stop. After this the vehicle will not be able to drive off.
Diagnostic depth
The software calculates a checksum on the data of the CAN message that has been received. It then compares this with the checksum attached to the same message by the sending node. A fault code is set if the checksums don't match for a specified amount of messages,
Mismatch in communication between the ECA and TMS. Possible reasons for the fault are a high load on the CAN bus or faulty ECA software.