BCU 523690.02 – S23/S68 Switches for Remote Control of Rockshaft (Right/Left), Fault Detected. John Deere System Advisory.

BCU 523690.02 (BCU )

Code: 523690.02



Error code BCU 523690.02 is triggered when the Basic Control Unit (BCU) of a John Deere vehicle detects unrealistic values from the switches used for remote control of the rockshaft on the right and left sides. This diagnostic trouble code suggests a potential issue with the switch mechanisms or their electrical connections, which may lead to incorrect operation or failure to respond during the control of the rockshaft.


The system may ignore the faulty signals from these switches, potentially leading to non-responsive or erratic behavior of the rockshaft adjustments, which could affect the tractor’s lifting and lowering operations.


  • Inspect the Remote Control Switches: Examine the S23 and S68 switches for physical damage or wear that could influence their functionality. Check for any debris or obstructions that might prevent the switches from returning to their neutral positions or causing them to stick.
  • Test Electrical Connections: Look at the wiring and connectors leading to these switches. Check for loose connections, corrosion, or damaged wires that might be causing incorrect readings.
  • Measure Signal Output: Use a multimeter to test the electrical signals output by the switches during activation. Compare these readings with the expected values to determine if the switches are operating within normal parameters.
  • Replace Faulty Switches: If testing confirms that the switches are faulty, replace them to ensure reliable operation. Make sure the new switches are correctly calibrated to send accurate signals to the BCU.
  • Reset the BCU and Clear Diagnostic Codes: After replacing the switches and ensuring all electrical connections are secure, reset the BCU to clear this and any other related diagnostic trouble codes. This step will also help reinitialize the system with the corrected settings.
  • Test System Functionality: Following the reset, conduct a comprehensive test to verify that the rockshaft operates correctly and responds accurately to commands from the newly installed switches.
  • Monitor System Post-Repair: Keep a close watch on the operation of the rockshaft and the functionality of the new switches over time to ensure no further issues occur.


Maintaining the functionality of control switches, such as those used for the remote operation of rockshafts, is essential for the precision and safety of agricultural machinery operations. Regular checks and immediate attention to any signs of malfunction are crucial to avoid operational delays and ensure the machinery performs efficiently and safely under all conditions. Proper maintenance and timely replacement of faulty components help extend the life and improve the reliability of the equipment.