Case IH 15257 - AST – AST (Auto Guidance / Steering control subsystem) / Steering Valve Controller (SVC): Incorrect steering valve controller configuration - Configured for incorrect steering valve type (switch state missing)

This fault indicates a configuration mismatch within the Advanced Steering (AST) / Auto Guidance system. The Steering Valve Controller (SVC) has detected that its software configuration does not match the physical steering valve installed on the machine, or a required switch state (such as the roading switch) is missing or incorrect. When this fault occurs, the electro-hydraulic steering is locked out for safety, and the tractor reverts to 'On-road mode' (fully manual hydraulic steering, typically 6 turns lock-to-lock).

• MAXXUM T4E
• VESTRUM CVX
• Case IH Magnum series (e.g., 180, 200, 220, 240, 250, 280, 310, 340, 380)
• Case IH Farmall series (e.g., 40, 45, 50, 115U Efficient Power)
• Case IH Vestrum CVX Series (e.g., 100, 110, 120, 130)
• Case IH Puma series
• Tractors utilizing the MTA CCM & APH Stage V MR architecture

1. 1

   Check if the instrument cluster (ICU3) displays 'On-road' or 'Off-road' mode to verify if electro-hydraulic features are disabled.

2. 2

   Ensure the roading switch is not stuck and is operating within a valid voltage range.

3. 3

   Verify configuration via the instrument cluster by navigating to the R1 module, menu H3, and selecting the AST system to check configuration channels and missing switch states.

4. 4

   Look for accompanying codes such as 15255 (Roading switch state crosscheck failed) or 15256 (Configured for incorrect steering valve type).

1. 1

   Attempt System Reset

   Place the tractor in PARK. Cycle the roading switch to the 'lock' position, then back to 'unlock'. Wait approximately 5 seconds for the fault to clear, then attempt to resume normal operation.

2. 2

   Reconfigure the SVC

   If the fault persists, the Steering Valve Controller must be reconfigured to match the physical valve. Using the instrument cluster (R1 module, menu H3) or the dealer electronic service tool (EST), verify the steering valve type selected in the software matches the hardware installed on the tractor.

3. 3

   Software Update/Reflash

   If the configuration is correct but the code remains, the Steering Valve Controller (SVC) software or the Advanced Steering Configuration dataset may be corrupted. Reflash the SVC to the latest software version (e.g., software version 2.02 or dataset version 3.2, depending on the model).

4. 4

   Inspect Wiring/Switches

   Check the wiring harness between the roading switch, the main steering controller, and the safety controller for open circuits that would cause a 'switch state missing' condition.