BCU 523692.09 – Incorrect CAN BUS Message for Upper Worklights on Cab Frame. John Deere System Advisory.

BCU 523692.09 (BCU )

Code: 523692.09



Error code BCU 523692.09 is triggered when there is an issue with data transfer between the power module PC0 and the Body Control Unit (BCU). This involves intermittent or non-existent reception of one or more CAN bus messages transmitted by the BCU to power module PC0, which controls the upper worklights on the cab frame. Such issues may be caused by problems like loose wiring or other communication disruptions within the CAN bus system.


The system may respond to this fault by temporarily disabling the upper worklights or alerting the operator through diagnostic indicators, preventing potential malfunctions due to incorrect or incomplete data transmission.


  • Inspect CAN Bus Connections: Start by checking the CAN bus connections between the BCU and power module PC0. Ensure all connections are secure and free from corrosion.
  • Test Wire Continuity and Security: Use diagnostic tools to test the continuity of the wires involved in the CAN bus system. Focus on identifying any loose or intermittent connections that could be disrupting communication.
  • Resolve Connectivity Issues: Tighten or replace any loose or damaged connectors or wiring found during the inspection.
  • Check for CAN Bus Interference: Ensure that there is no electromagnetic interference affecting CAN bus communication. Keep wiring away from high voltage lines or equipment that may emit strong electromagnetic fields.
  • Reset and Reconfigure Systems: After ensuring all physical connections are intact and secure, reset the CAN bus system and reconfigure settings if necessary to ensure proper communication protocols are followed.
  • Monitor System Performance: Continuously monitor the system to ensure that communication has been fully restored and that no further message errors are occurring.


Maintaining clear and correct communication pathways in complex vehicle systems like those in agricultural machinery is critical for ensuring reliable operation. Regular system checks and updates are essential to prevent miscommunications and ensure that each component functions correctly within the overall system architecture.