ATC 000923.19 – Fan Motor Incorrect CAN BUS Message. John Deere System Advisory.

ATC 000923.19 (ATC 923.19)

Code: 000923.19

Shortcode: 923.19


The error code, ATC 000923.19, is triggered when the outputs for switching the fan motors (M07 and M10) are energized by more than one control unit, leading to potential conflicts or errors in the operation of the fan motors. This condition suggests a misconfiguration or communication error within the CAN BUS system, where multiple control units are inadvertently attempting to control the same outputs.


This miscommunication may lead to erratic operation of the fan motors, including sporadic turning on and off, which can affect the cooling efficiency of the system and potentially lead to overheating of critical components.


  • Diagnose CAN BUS Communication: Use diagnostic tools to analyze the CAN BUS communications and identify all control units sending commands to the fan motors. Determine the source of the conflict and which control units are involved.
  • Inspect Configuration Settings: Review the configuration settings of the involved control units to ensure they are set correctly and are not duplicating commands for the fan motors.
  • Correct Software Settings: If necessary, reprogram or update the software settings in the control units to correct any misconfiguration or to ensure proper communication hierarchy and command protocols.
  • Test Fan Motor Operation: After making the necessary adjustments, test the fan motor operation to ensure it responds appropriately to control commands and that the issue has been resolved.
  • Monitor System for Further Issues: Continue to monitor the system to ensure no further CAN BUS communication errors occur and that the fan motors operate reliably under normal conditions.


Maintaining clear and correct communication between control systems is crucial for the safe and efficient operation of machinery. Regular monitoring and maintenance of the CAN BUS and associated electronics are essential to prevent communication failures and ensure that the equipment operates smoothly. Addressing communication issues promptly is key to minimizing downtime and maintaining operational efficiency.