Critical internal fault in the control unit (CRC checksum faulty)
â–¶ How to fix
Clear the fault code and switch the voltage off and on. If the fault code is regenerated, renew the control unit.
What you'll see
No driver-visible symptom recorded.
System reaction
For vehicles with an automatic gearbox or automatic manual gearbox: The system goes into locked gear and if the vehicle has automatic clutch, the engine is emergency shut-down. For vehicles with retarder: Retarder braking does not work.The yellow retarder warning is displayed in the instrument cluster. When this fault code has been generated, the control unit must restart in order for the retarder to work again.
Diagnostic depth
Detection
Continously check of CRC.
Possible cause
The control unit is defective or the software has been modified.