CCU 523844.12 – Differential Lock Braking Disabled

CCU 523844.12 (CCU )

Code: 523844.12



This fault code indicates that the differential lock switch has been engaged (closed) for more than 5 minutes continuously. The differential lock is intended for temporary use to provide extra traction in difficult conditions. Prolonged engagement can lead to overheating and excessive wear on the differential components.


The control unit disables the differential lock braking to prevent potential damage due to prolonged engagement.


  • Check Differential Lock Switch: Inspect the differential lock switch for proper operation. Ensure it disengages correctly after use.
  • Educate Operators: Train operators to use the differential lock only when necessary and to disengage it promptly after the need for additional traction has passed.
  • Inspect Differential Components: Check the differential and associated components for any signs of wear or overheating due to prolonged engagement. Replace any damaged parts as needed.
  • System Reset and Testing: After addressing the issue, reset the system and perform tests to ensure the differential lock engages and disengages correctly.


Proper use of the differential lock is crucial for maintaining the longevity of the differential system. Regular checks and operator training can prevent misuse and extend the life of the equipment.

Control Units: John Deere

John Deere Parts
John Deere Logo