SSU 523821.02 – Vehicle Mismatch

SSU 523821.02 (SSU )

Code: 523821.02



This diagnostic trouble code (DTC), SSU 523821.02, is triggered when the Steering System Control Unit (SSU) detects that the vehicle model number or loopback wire does not match the AutoTrac configuration. This indicates a mismatch between the vehicle’s configuration and the AutoTrac settings.


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


Verify Vehicle Configuration:

  • Check the vehicle model number and loopback wire configuration.
  • Ensure that the vehicle’s configuration matches the AutoTrac settings as per the manufacturer’s guidelines.

Update Configuration:

  • If there is a mismatch, update the AutoTrac configuration to match the vehicle model number and loopback wire settings.

Update Software:

  • Ensure that the SSU and AutoTrac software are up-to-date. Apply any available firmware updates to improve system compatibility.

Consult Technical Support:

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


  • Regular verification of system configurations can help prevent mismatches.
  • Ensuring the vehicle and AutoTrac settings are correctly aligned is crucial for reliable operation of the guidance system.

Control Units: John Deere

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