BCU 523692.04 – Upper Worklights on Cab Frame On, Current Too High at Power Module PC0. John Deere System Advisory.

BCU 523692.04 (BCU )

Code: 523692.04



Error code BCU 523692.04 is triggered when the Power Module PC0 in a John Deere vehicle measures a current exceeding 15 amps at lead 1029 for the upper worklights on the cab frame while they are activated. This diagnostic trouble code indicates a short to ground within the circuit, a serious condition that can lead to excessive current draw, potentially causing overheating, damage to electrical components, or even a fire hazard.


To prevent damage, the power module may automatically deactivate the affected circuit, causing the upper worklights to cease functioning. This protective response helps mitigate the risk of further electrical failures or potential safety hazards.


  • Inspect Wiring and Connections: Examine the wiring and connectors for the upper worklights to identify any signs of damage, wear, or corrosion that could contribute to a short circuit. Look specifically for exposed wires or connectors that could be making unintended contact with the vehicle’s frame or other metal components.
  • Measure Current Flow: Use a clamp meter to measure the current flow through lead 1029 while the worklights are switched on, to confirm the excessive current draw.
  • Identify and Repair Short Circuits: Locate the source of the short to ground and make necessary repairs. This may involve replacing damaged wires or connectors, and ensuring all wiring is correctly insulated and routed away from potential hazards.
  • Evaluate Power Module PC0: Assess the power module for any signs of damage from the excessive current, such as burnt components or melted connections. Replace the module if it has been compromised.
  • Reset the Power Module and BCU: After making the necessary repairs, reset the power module and the BCU to ensure the system recognizes the repairs and to clear the diagnostic trouble code.
  • Test System Functionality: After the reset, activate the upper worklights to verify that they are functioning correctly and that the current draw is within safe limits. Monitor the repaired circuit closely to ensure the issue does not recur.
  • Regular Monitoring and Maintenance: Implement a routine inspection schedule for the vehicle’s electrical systems to detect and resolve any emerging issues before they lead to significant failures or safety hazards.


Maintaining the electrical integrity of key operational features such as worklights is critical for safe operation. Regular inspections and immediate repairs of any electrical malfunctions are crucial in preventing operational disruptions and enhancing the safety and effectiveness of machinery in various operating conditions. Proper maintenance and timely replacement of faulty components help extend the life and improve the reliability of the vehicle’s electrical systems.