BCU 523758.11 – S121 Remote Control Switch for Rear PTO (Right), Fault. John Deere System Advisory.

BCU 523758.11 (BCU )

Code: 523758.11



Error code BCU 523758.11 is triggered when the Basic Control Unit (BCU) of a John Deere vehicle detects an unrealistic value from the switch used for remote control of the rear Power Take-Off (PTO) on the right side. This diagnostic trouble code suggests that the switch may be malfunctioning, possibly due to internal electrical issues such as a short circuit, corrosion, or wear, or it could be providing incorrect signals due to a misconfiguration or external interference.


The fault in the remote control switch could lead to improper functioning of the rear PTO, affecting its ability to engage or disengage correctly. This could impact operations that rely on PTO-powered implements, potentially leading to reduced productivity or unsafe working conditions.


  • Inspect the Remote Control Switch: Check the remote control switch for any signs of physical damage or wear that could affect its operation. Look for corrosion on the terminals that might impede signal transmission.
  • Test Electrical Functionality: Use a multimeter to test the electrical functionality of the switch. Verify that it is operating within the manufacturer’s specified electrical parameters.
  • Replace or Repair Faulty Switch: If the switch is found to be defective, replace or repair it to ensure reliable operation. Ensure all connections are secure and properly insulated after making repairs or replacements.
  • Reconfigure or Recalibrate the System: If necessary, reconfigure or recalibrate the settings related to the rear PTO operation in the BCU to ensure that it recognizes the correct inputs from the newly repaired or replaced switch.
  • Reset the BCU: Clear any diagnostic trouble codes and reset the BCU to ensure it processes the inputs from the switch correctly and resumes normal operation.
  • Test the System Functionality: After the repairs and any system adjustments, test the rear PTO system to ensure that it responds correctly to commands from the remote control switch. Confirm that the PTO engages and disengages as expected without any delays or issues.
  • Regular Maintenance Checks: Integrate regular checks of the PTO system and its controls into your maintenance routine. Keeping the system well-maintained can help avoid similar issues in the future and ensure consistent performance.


Regular maintenance and prompt attention to issues with control systems are crucial for maintaining the safety and efficiency of agricultural machinery. Ensuring that all components, especially those involved in critical functions like PTO operation, are in optimal condition helps avoid operational delays and enhances the overall productivity and safety of the equipment.