BCU 523692.01 – Upper Worklights on Cab Frame, Power Supply Fault at Power Module PC0. John Deere System Advisory.

BCU 523692.01 (BCU )

Code: 523692.01



Error code BCU 523692.01 is activated when the Power Module PC0 in a John Deere vehicle measures a voltage of less than 3 volts at lead 0792, which supplies power to the upper worklights on the cab frame, while these lights are switched on. This diagnostic trouble code indicates an issue with the power supply, such as an inadequate voltage output from the power module or a fault within the wiring or connections, which can prevent the worklights from functioning properly.


The lower voltage may cause the upper worklights to fail to illuminate or to perform suboptimally, potentially compromising visibility during operations that require additional lighting.


  • Inspect Power Module PC0: Check the power module for any signs of damage or malfunction that might be causing the reduced voltage output. Ensure that the module is functioning correctly and is capable of delivering the required voltage.
  • Examine Wiring and Connections: Look at the wiring and connectors between Power Module PC0 and the upper worklights. Check for loose connections, corrosion, or damage that could be contributing to voltage drop.
  • Measure Voltage Output: Use a multimeter to verify the voltage at lead 0792 when the worklights are switched on. This will help confirm the presence of a voltage supply issue.
  • Repair or Replace Faulty Components: If any faults in the power module, wiring, or connectors are identified, make the necessary repairs or replacements to ensure the correct voltage is supplied to the worklights.
  • Reset the Power Module and BCU: After repairs are made, reset the power module and the BCU to ensure that they recognize the repairs and to clear any associated diagnostic trouble codes.
  • Test System Functionality: Following the reset, test the upper worklights to confirm that they are receiving adequate power and are functioning correctly. Monitor the voltage during operation to ensure stability.
  • Regular Maintenance and Checks: Implement regular maintenance checks to monitor the health of the electrical system, focusing on preventing similar issues in the future. Routine inspections can help catch potential problems early, preventing downtime and ensuring safe operations.


Proper maintenance of vehicle electrical systems is crucial for safe and efficient operation. Ensuring that all components are regularly checked and maintained helps prevent issues related to inadequate power supply and can extend the life and performance of the vehicle’s electrical and lighting systems. Regular diagnostic checks and immediate attention to any signs of electrical malfunction are key to maintaining operational readiness and safety.