BCU 303053.03 – B26 Sensitivity Potentiometer, Signal Voltage Too High. John Deere System Advisory.

BCU 303053.03 (BCU )

Code: 303053.03



Error code BCU 303053.03 is issued when the Basic Control Unit (BCU) of a John Deere vehicle detects a signal voltage over 4.75 V at the input of the B26 sensitivity potentiometer during the calibration of the hitch control. This high voltage reading indicates a potential issue with the potentiometer itself, such as a fault in its wiring or a failure in the electronic components that regulate its output, which can affect the accuracy and performance of hitch control operations.


The system may respond to this abnormal signal by halting the calibration process, as the incorrect voltage could lead to improper hitch control settings, potentially affecting operational accuracy and safety.


  • Inspect the Sensitivity Potentiometer: Check the B26 sensitivity potentiometer for any signs of damage or wear that might affect its function. Look for physical defects on the potentiometer and ensure it is properly mounted and connected.
  • Test Electrical Connections: Examine the wiring and connectors leading to the potentiometer. Look for signs of corrosion, loose connections, or damaged wires that could contribute to abnormal voltage readings.
  • Measure Signal Voltage: Using a multimeter, measure the voltage at the signal input of the potentiometer to verify that it exceeds the normal operating range. This measurement will help confirm the diagnostic code’s accuracy.
  • Replace Faulty Potentiometer: If the potentiometer is found to be faulty or the wiring is irreparable, replace the necessary components to ensure reliable operation.
  • Recalibrate Hitch Control: After repairing or replacing the potentiometer, recalibrate the hitch control system according to the manufacturer’s specifications to ensure it operates correctly with the new or repaired components.
  • Reset the BCU and Clear Diagnostic Codes: Reset the BCU to clear any stored error codes and reinitialize the system settings. This step will help verify that the issue has been resolved and that the system acknowledges the repairs.
  • Monitor System Post-Repair: Continue to monitor the operation of the hitch control to ensure that the sensitivity potentiometer functions correctly and that no further high voltage issues are detected.


Regular maintenance and inspection of control system components like sensitivity potentiometers are crucial for maintaining the precision and safety of machinery operations. Addressing issues promptly when detected helps prevent operational inefficiencies and ensures that the machinery continues to perform optimally. Proper functioning of these components is essential for precise control and reliability of the vehicle’s hitch and related systems.