BCU 523703.03 – B19 Right Draft Sensor, Voltage Too High During Calibration. John Deere System Advisory.

BCU 523703.03 (BCU )

Code: 523703.03



Error code BCU 523703.03 is triggered when the Basic Control Unit (BCU) of a John Deere vehicle detects an abnormally high voltage, exceeding 4.75 volts, at the signal input of the right draft sensor during its calibration phase. This diagnostic trouble code suggests a potential malfunction within the draft sensor circuit, which may include issues such as electrical interference, a faulty sensor, or improper wiring that is causing elevated voltage levels.


The high voltage detection can lead to inaccurate readings from the right draft sensor, potentially affecting the tractor’s hitch control system. This could impair the tractor’s ability to effectively manage implements attached to the hitch, impacting performance and operational efficiency.


  • Inspect the Right Draft Sensor and Associated Wiring: Examine the sensor and its wiring for signs of damage, corrosion, or other faults that might contribute to high voltage readings.
  • Test Sensor Voltage: Utilize a multimeter to measure the voltage at the draft sensor’s input during calibration to confirm the high voltage condition.
  • Replace or Repair Faulty Components: If the sensor or wiring is damaged or faulty, replace or repair these parts to ensure the correct functioning of the draft sensor.
  • Re-calibrate the Draft Sensor: Following any component replacement or repair, recalibrate the right draft sensor to ensure it delivers accurate data to the BCU.
  • Reset the BCU: Clear any stored diagnostic trouble codes and reset the BCU to ensure it properly recognizes the repaired system and reinitializes its settings.
  • Test the System Functionality: Conduct tests to verify that the draft sensor operates correctly post-repair, ensuring that it no longer exhibits high voltage readings during calibration.
  • Regular System Checks and Preventive Maintenance: Incorporate regular inspections and maintenance checks for the draft sensor and related systems to prevent recurrence of similar issues. Early detection and resolution of potential problems can help maintain optimal machinery performance and reliability.


Proper sensor function is critical for precision agricultural operations that rely on accurate data inputs for effective machinery control. Regular maintenance and timely intervention when issues are detected are essential to prevent disruptions and ensure continued efficient operation of equipment.