Case IH 15311 - AST – Steering Valve Controller (SVC): Incorrect steering valve controller configuration - Auto-calibration configuration

Auto-calibration configuration data stored within the steering system is missing, invalid, or corrupted. The controller does not have the correct baseline parameters (such as PWM signal values and wheel angle sensor limits) required to safely operate the automated steering (AccuGuide) system.

• MAXXUM T4E
• VESTRUM CVX
• Magnum
• Steiger
• Puma
• Maxxum
• Farmall
• 8120
• 7240
• 8240
• 9240

1. 1

   Check for accompanying SVC fault codes (e.g., 15312, 15313, or 15314) that might indicate a hard failure rather than just a calibration issue

2. 2

   Ensure the tractor's hydraulic oil is at normal operating temperature (cold oil will cause the calibration to fail or generate incorrect data)

3. 3

   Verify that the Wheel Angle Sensor (WAS) linkage on the steering axle is intact, not bent, and securely mounted

4. 4

   Ensure the AFS display (e.g., Pro 700 / Pro 1200) and the Nav Controller are properly communicating on the ISOBUS

1. 1

   Preparation

   Drive the machine to a wide-open, flat, and level area. Ensure the hydraulic fluid is at operating temperature.

2. 2

   Access Calibration Menu

   On the AFS Pro 700 / Pro 1200 display, navigate to CALIBRATION > CALIBR.

3. 3

   Rear Wheel / Steered Wheel Position Calibration

   Select the wheel position calibration. Drive the machine perfectly straight. Press 'OK' on the display to save the center position.

4. 4

   Steering Valve Calibration

   Select the Steering Valve Calibration from the menu. Follow the on-screen prompts. The system will automatically command the steering valve to turn the wheels left and right to learn the correct proportional valve (PWM) command values.

5. 5

   Roll Offset Calibration

   Navigate to CALIBRATION > NAV and perform the roll calibration to compensate for any minor variations in the navigation controller's placement (if required).

6. 6

   Verification

   Engage the auto-guidance system on a test swath to ensure the 'GPS - ISO' steering mode activates and the fault code clears.

7. 7

   Dealer Intervention

   If the calibration repeatedly fails to save, the Steering Valve Controller may have an internal EEPROM failure. A dealer will need to use the CNH Electronic Service Tool (EST) to reflash the controller or replace the steering valve assembly.