BCU 303053.04 – B26 Sensitivity Potentiometer, Signal Voltage Too Low. John Deere System Advisory.

BCU 303053.04 (BCU )

Code: 303053.04



Error code BCU 303053.04 is triggered when the Basic Control Unit (BCU) of a John Deere vehicle detects a signal voltage below 0.25 V at the input of the B26 sensitivity potentiometer during the calibration of the hitch control. This low voltage reading suggests an issue such as a poor connection, a fault in the potentiometer itself, or a problem in the associated wiring, which can critically affect the calibration and operation of the hitch control.


The calibration process for the hitch control may be interrupted due to the inaccurate voltage signal, potentially resulting in improper hitch operation. This can lead to inefficiencies or safety risks during equipment use.


  • Inspect the Sensitivity Potentiometer: Examine the B26 sensitivity potentiometer for signs of wear, damage, or malfunction. Ensure that it is securely mounted and connected.
  • Check Wiring and Connections: Look at all connections to the potentiometer, especially focusing on potential corrosion, loose wires, or damaged connectors that could contribute to voltage drops.
  • Measure Signal Voltage: Use a multimeter to confirm the voltage at the signal input of the potentiometer. This will help verify the problem indicated by the diagnostic code.
  • Repair or Replace Faulty Components: If any issues are identified with the potentiometer or wiring, make the necessary repairs or replacements to ensure correct voltage transmission.
  • Recalibrate Hitch Control: Once the potentiometer is fixed or replaced, recalibrate the hitch control system according to the manufacturer’s guidelines to ensure accurate operation.
  • Reset the BCU and Clear Diagnostic Codes: After the repairs, reset the BCU to ensure that it recognizes the repair and clears the error code. This also helps to reinitialize the system with the corrected settings.
  • Monitor Operation Post-Repair: Keep a close watch on the functionality of the hitch control to make sure the sensitivity potentiometer is operating as expected without further voltage issues.


Maintaining accurate control system sensors and connections is crucial for the performance and safety of agricultural machinery. Regular inspections and prompt repairs of components like the sensitivity potentiometer help prevent potential operational failures and ensure the equipment functions efficiently. These proactive measures are essential for the longevity and reliability of the vehicle’s systems.