BCU 523691.19 – Incorrect CAN BUS Message Affecting Lower Worklights on Cab Frame. John Deere System Advisory.

BCU 523691.19 (BCU )

Code: 523691.19



Error code BCU 523691.19 occurs when the output for controlling the lower worklights on the cab frame (E20/R and E20/L) or the xenon (HID) worklights on cab frame (E36/R and E36/L) is erroneously energized by more than one control unit. This indicates a communication error or configuration issue within the CAN BUS system, where multiple signals to activate the worklights overlap or conflict, leading to potential operational discrepancies.


The system may respond by deactivating the conflicting outputs or alerting the operator via diagnostic indicators to prevent improper operation of the worklights, potentially leading to issues like simultaneous conflicting commands or electrical overload.


  • Diagnose CAN Bus Communication: Utilize diagnostic tools to trace and diagnose the communication paths within the CAN bus system. Identify any misconfigurations or errors that are causing multiple control units to energize the same output.
  • Reconfigure System Settings: Adjust the settings in the control units to ensure that only the correct signals are sent for the operation of the worklights. Remove any duplicate configurations or correct misassigned controls.
  • Inspect and Secure Wiring Connections: Verify that all wiring connections are correctly and securely made, as poor connections can sometimes mimic or cause communication errors.
  • Test System Operation: After making adjustments, thoroughly test the system to ensure that the worklights operate as intended, with signals correctly issued by the appropriate control unit.
  • Update Software/Firmware: If necessary, update the software or firmware of the involved control units to enhance their communication protocols and prevent future issues.


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.