BCU 523753.18 – M08 Stepper Motor for Hitch, Raising Deadband Too Low During Calibration. John Deere System Advisory.

BCU 523753.18 (BCU )

Code: 523753.18



Error code BCU 523753.18 is activated when the Basic Control Unit (BCU) of a John Deere vehicle detects that the raising deadband (the minimal play between the adjustment cam of the stepper motor and the raise valve of the hitch valve) identified during the calibration process is below the specified minimum tolerance. This condition indicates that the components are too tightly configured, which can lead to excessive wear, potential binding, or reduced responsiveness in the hitch mechanism.


A too low deadband may cause the hitch system to react too quickly or with too much sensitivity to commands, potentially leading to erratic or unstable hitch movements. This overly tight configuration can accelerate wear on mechanical components and affect the longevity and reliability of the hitch system.


  • Inspect and Adjust Stepper Motor and Hitch Valve Linkage: Examine the mechanical linkage between the stepper motor and the hitch raise valve. Adjust the setup to increase the deadband to within the manufacturer’s recommended specifications.
  • Re-calibrate the Hitch System: After making the necessary mechanical adjustments, recalibrate the hitch system to ensure that the adjustments have correctly set the deadband, improving control and operation.
  • Reset the BCU: Clear any related diagnostic trouble codes and reset the BCU to ensure it accurately recognizes and adjusts to the changes made during recalibration.
  • Test Hitch Operation: Conduct operational tests to ensure that the hitch raises and lowers smoothly and responsively according to operator inputs, and that it maintains stability under various loads.
  • Monitor System Performance: After recalibration and testing, continue to monitor the hitch system closely to ensure it operates as expected without excessive speed or sensitivity.
  • Routine Maintenance and Inspections: Include regular inspections and maintenance checks of the hitch system in your ongoing maintenance routines. Pay particular attention to signs of wear or damage on components that could be impacted by the tight settings.
  • Documentation and Operator Training: Document the adjustments made and the outcomes of recalibration. Educate operators on the importance of observing the hitch system’s performance and reporting any irregularities promptly.


Maintaining optimal deadband settings in the hitch control system is crucial for ensuring precise and efficient operation of agricultural machinery. Regular adjustments and calibrations help in preventing mechanical wear and tear and preserving the functionality and effectiveness of the hitch system, thereby enhancing the overall performance and productivity of the equipment.