AIC 521133.02 – CommandQuad™ Range Switch B Circuit Conflict. John Deere AIC System Alert.

AIC 521133.02 (AIC )

Code: 521133.02



This error code, AIC 521133.02, indicates a malfunction in the CommandQuad™ transmission system where the range switch B is experiencing a circuit conflict. The issue arises because the ON and OFF contacts of the switch are registering the same value, which can confuse the transmission system’s control logic, leading to improper gear selection or operational errors.


To safeguard against potential transmission damage and to maintain safety, the control unit has placed the vehicle into a recoverable PARK position, halting further movements until the issue is resolved.


  • Inspect range switch B for mechanical faults such as sticking or failure to return to a neutral position. Check for debris, wear, or damage that might be causing the contacts to align incorrectly.
  • Utilize diagnostic equipment to test the electrical functionality of the switch, ensuring that the ON and OFF states can be distinctly and reliably identified by the control system.
  • Examine the wiring and connectors linked to range switch B for signs of damage, loose connections, or other faults that could be causing electrical interference or misreadings.
  • Replace the malfunctioning switch or repair any identified issues within the circuit. Ensure that all repairs are conducted in accordance with manufacturer specifications and that the switch is properly calibrated.
  • After corrective actions are completed, recalibrate the associated transmission settings if necessary and conduct thorough testing to verify that the vehicle can safely exit the PARK position and that the switch operates correctly across its range of functions.


Maintaining the operational integrity of transmission range switches is critical for the reliable and safe operation of vehicles. Frequent inspections and immediate attention to any detected issues are crucial in preventing operational disruptions and ensuring long-term equipment efficiency and safety.