BCU 523703.03 – High Voltage Detected in Right Draft Sensor During Calibration. John Deere System Advisory.

BCU 523703.03 (BCU )

Code: 523703.03



The diagnostic trouble code BCU 523703.03 is activated when the basic control unit (BCU) detects an abnormally high voltage, above 4.75 volts, at the signal input of the right draft sensor during calibration. Such a high voltage reading typically indicates a malfunction within the draft sensor circuit, which could be caused by issues such as electrical shorts, incorrect wiring, or a fault within the sensor itself.


To prevent potential damage or inaccuracies in measurement, the BCU may temporarily disable the sensor or related systems until the fault is corrected, affecting the precision of draft control operations in agricultural machinery.


  • Inspect Sensor Wiring and Connections: Thoroughly examine the wiring and connections associated with the right draft sensor. Look for signs of damage, short circuits, or incorrect connections that could contribute to high voltage readings.
  • Test the Sensor and Circuit: Use a multimeter or similar diagnostic tool to test the voltage levels and continuity in the sensor circuit. Identify any discrepancies from the normal operational range.
  • Replace or Repair Faulty Components: If any component of the sensor circuitry is found to be defective, replace or repair it to restore proper function and voltage levels.
  • Re-calibrate the Sensor: After making necessary repairs, recalibrate the draft sensor to ensure it provides accurate and reliable readings.
  • Ensure Proper System Integration: Verify that the sensor is correctly integrated with the BCU and other related systems, ensuring there is no interference or misconfiguration that might affect its performance.


Regular maintenance and calibration of sensors are crucial for the accurate operation of machinery, especially in precision-dependent settings like agriculture. Addressing voltage issues promptly can help maintain operational efficiency and extend the life of both the sensor and the equipment it helps control.