BCU 000746.31 – Differential Lock Solenoid Valve Fault. John Deere System Advisory.

BCU 000746.31 (BCU 746.31)

Code: 000746.31

Shortcode: 746.31


Error code BCU 000746.31 is triggered when the Basic Control Unit (BCU) of a John Deere vehicle detects an open circuit in the differential lock solenoid valve. This fault indicates a disruption in the electrical path that activates the solenoid, which is crucial for engaging the differential lock. An open circuit can prevent the differential lock from functioning, potentially affecting the vehicle’s traction and handling, especially under conditions requiring enhanced stability.


Upon detecting this fault, the BCU may deactivate the differential lock mechanism to prevent erratic behavior and may alert the operator through dashboard warning lights or system messages.


  • Inspect Solenoid Valve and Wiring: Examine the differential lock solenoid valve for any signs of damage, wear, or corrosion. Check all associated wiring and connectors for breaks, wear, or disconnections that could cause an open circuit.
  • Test Solenoid Functionality: Utilize a multimeter to test the continuity of the solenoid coil and the integrity of the wiring from the BCU to the solenoid valve. This will help confirm the presence of an open circuit.
  • Repair or Replace Faulty Components: If any damage or disconnection is found during the inspection, repair the wiring or replace the solenoid valve to restore proper function.
  • Check System Operation: After repairs, test the differential lock operation to ensure that the solenoid is engaging correctly and that the differential lock is functioning as intended.
  • Reset the BCU and Clear Diagnostic Codes: Clear any fault codes from the BCU and reset the system to ensure all electronic systems are communicating properly without any lingering errors.


Regular maintenance and timely inspection of the differential lock system and its electrical components are crucial for ensuring the reliability and safety of your John Deere vehicle, particularly in rugged or variable terrain conditions. Ensuring that all components are in good working order helps maintain optimal vehicle performance and prevents potential operational issues.