Case IH 15994 - AST – AST (Advanced Steering) module: NAV option is configured as 'not present' but NAV controller is detected online

The tractor's CAN bus is physically detecting the presence of a Navigation (NAV) controller (used for Autoguidance/Autosteer), but the steering system's software is configured to expect that the NAV option is not installed on the machine.

• MAXXUM T4E
• VESTRUM CVX
• Maxxum
• Puma
• Optum
• Steiger
• Quadtrac

1. 1

   Verify if the tractor is physically equipped with a Navigation Controller (NAV II or NAV III)

2. 2

   Check service history to determine if a NAV controller was recently added, or if the AST module was recently replaced or reprogrammed

3. 3

   Verify the current configuration settings in the instrument cluster display (H menus) to see what the AST system is currently expecting

1. 1

   Turn the key on to power the instrument cluster and controllers.

2. 2

   Enter the configuration mode by navigating the "H menus" using the switches on the instrument cluster.

3. 3

   Navigate to the R1 module, then to menu H3.

4. 4

   Select the AST system and press the dimming key to accept the menu selection.

5. 5

   Observe the lower LCD section of the display, which will show “ch - - ”.

6. 6

   Access the configuration settings and change the NAV option from "not present" to "present" so that it matches the tractor's actual installed equipment.

7. 7

   Save the configuration and cycle the key power to clear the fault code.

8. 8

   Perform an AST Steering Calibration if required after making configuration changes.