SSU 523826.12 – Excessive Hysteresis in AutoTrac Steering

SSU 523826.12 (SSU )

Code: 523826.12



This diagnostic trouble code (DTC), SSU 523826.12, is triggered when the Steering System Control Unit (SSU) detects that the wheel angle sensor-axle is not detecting actual steering motion within the allotted time during calibration. This fault tends to occur as additional hours accrue and the steering mechanics loosen.


When this error is detected, the AutoTrac steering system may not function accurately, leading to potential issues with vehicle guidance and control.


Inspect Steering Mechanics:

  • Check the steering mechanics for signs of wear or looseness that could contribute to excessive hysteresis.
  • Tighten or replace any worn components as necessary.

Verify Sensor Functionality:

  • Ensure that the wheel angle sensor-axle is functioning properly and providing accurate readings.
  • Use diagnostic tools to measure the sensor’s response time and accuracy.

Perform Calibration:

  • Recalibrate the steering system to ensure accurate readings from the wheel angle sensor-axle.
  • Follow the manufacturer’s guidelines for the calibration process.

Update Software:

  • Ensure that the SSU software is up-to-date. Apply any available firmware updates to improve calibration accuracy and system performance.

Replace Faulty Components:

  • If the wheel angle sensor-axle or related components are found to be defective, replace them with new, genuine parts.

Consult Technical Support:

  • If the error persists after performing the above steps, consult technical support or the manufacturer for further assistance.


  • Regular maintenance and inspection of the steering system components can help prevent hysteresis issues.
  • Ensuring proper calibration and tightness of steering mechanics is crucial for reliable steering performance.

Control Units: John Deere

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