BCU 523843.03 – Quick Withdrawal Switch, Voltage Too High. John Deere System Advisory.

BCU 523843.03 (BCU )

Code: 523843.03



Diagnostic trouble code BCU 523843.03 is generated when the Basic Control Unit (BCU) detects that the voltage at the signal input of the quick withdrawal switch exceeds 10.5 volts, indicating a malfunction within the circuit of the quick withdrawal switch. Additionally, this code may be triggered due to an operating error, such as the switch being actuated during the bulb check, which can artificially elevate voltage readings temporarily.


Upon detection of this fault, the system might deactivate the quick withdrawal switch’s function to prevent any unintended operations caused by the faulty signal. An alert may also be issued on the operator’s control panel to indicate the high voltage issue.


  • Inspect Wiring and Connections: Examine the wiring and connectors to the quick withdrawal switch for any damage, corrosion, or loose connections that could result in high voltage readings.
  • Monitor Switch Activation: Ensure that the switch is not being inadvertently activated during system checks like the bulb check, which could falsely trigger this diagnostic code.
  • Test the Switch and Circuit: Use a multimeter to verify the voltage levels at the quick withdrawal switch during normal operation. This will help determine if the high voltage is a persistent issue or a temporary anomaly.
  • Replace Faulty Components: If the switch or any associated circuit components are found to be defective and contributing to high voltage levels, replace these components to correct the fault.
  • Reset and Test the System: After conducting repairs, reset the system to clear the diagnostic code and conduct thorough testing to ensure the switch operates within normal voltage parameters under all conditions.


Regular system diagnostics and careful monitoring of the operation of switches and other control inputs are crucial for maintaining the safe and efficient functionality of machinery. Misinterpretations due to temporary conditions such as bulb checks should be differentiated from genuine electrical faults. Proper training for operators on the correct usage of switches during all phases of operation can help minimize false alarms and ensure reliability.

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