ACU 523966.31 – Activation of Come Home Mode

ACU 523966.31 (ACU )

Code: 523966.31



This error code, ACU 523966.31, is generated when the ‘Come Home’ mode is activated in the transmission system. This mode is typically enabled as a protective measure when the system detects a significant malfunction or operational anomaly that could prevent normal functioning.


Upon activation, the control unit defaults the transmission to ‘Come Home’ mode, which allows the vehicle to operate at reduced functionality, ensuring that the operator can safely drive the machine to a service location or home base for maintenance.


  • Investigate the underlying causes that triggered the ‘Come Home’ mode. This may involve checking for transmission faults, sensor malfunctions, or other critical issues indicated by diagnostic trouble codes.
  • Perform a thorough inspection and diagnostic check of the transmission system to identify and resolve any faults or abnormalities.
  • Reset the transmission system only after ensuring all issues have been addressed. It may be necessary to use specialized diagnostic equipment to clear the mode and reset the system.
  • Update any software associated with the transmission control unit, as updates may include fixes that prevent false triggers of the ‘Come Home’ mode.
  • If recurring activations of ‘Come Home’ mode occur, it is advisable to consult with a John Deere certified technician who can provide a more comprehensive diagnosis and necessary repairs.


The ‘Come Home’ mode is an essential safety feature designed to protect the vehicle and operator from further damage or danger. Regular maintenance and immediate attention to any transmission alerts are crucial to ensure the continued reliability and safety of the machinery.