ACU 523962.31 – MFWD Speed Discrepancy Detected

ACU 523962.31 (ACU )

Code: 523962.31



Error code ACU 523962.31 is activated when there is an invalid speed reading in the Mechanical Front-Wheel Drive (MFWD) system, exclusive to vehicles equipped with AutoPowr/IVT transmissions. This indicates that the speed data does not align with expected parameters, possibly due to sensor errors or calibration issues.


Due to the unreliable speed data, the control unit has automatically disabled the traction control system to prevent potential mishandling or safety hazards that could arise from incorrect drivetrain responses.


  • Verify the functionality and calibration of the speed sensors in the MFWD system. Ensure they are accurately measuring and reporting speeds.
  • Check the connections and wiring to the speed sensors for any signs of damage, wear, or disconnection that might be affecting their performance.
  • Use diagnostic tools to capture live data from the MFWD system to pinpoint discrepancies and assess whether sensor readings align with actual vehicle speeds.
  • If sensor recalibration is needed, follow the manufacturer’s guidelines to ensure accurate setup. Consider updating any related software or firmware that may improve sensor accuracy and system response.
  • Should the issue persist despite sensor checks and recalibrations, it may be necessary to replace faulty sensors or other related components in the MFWD system.


Maintaining accurate speed readings in the MFWD system is crucial for optimal drivetrain performance and safety, particularly in vehicles with advanced transmission systems like AutoPowr/IVT. Regular maintenance and prompt attention to drivetrain and sensor anomalies are essential for ensuring reliable operation and preventing traction-related issues.