Case IH 2273 – ZDC: TireCircumference Signal Not Within Allowed Range

The ZDC module is receiving a CAN bus message (DispVehicleConfig2) from the tractor's display monitor where the TireCircumference signal is 'Not Within Allowed Range'. The transmission controller rejects the value and logs this code to prevent erratic shifting or incorrect speed calculations.

• Steiger T4B
• Case IH Magnum CVT series
• Case IH Steiger CVT / AFS Connect series
• Case IH Puma CVX / CVXDrive series
• Case IH Optum CVXDrive series
• Case IH Maxxum CVX series

1. 1

   Verify the currently entered rolling tire circumference in the Vehicle Configuration / Tire Setup menu on the AFS display

2. 2

   Measure the physical rolling circumference of the rear tires (or consult the tire manufacturer's data book) to ensure the entered value matches reality

3. 3

   Check for accompanying CAN communication loss codes (e.g., loss of DispVehicleConfig2) which may indicate a wiring harness short or open rather than a configuration error

4. 4

   Verify that the software versions of the AFS Display and the ZDC are compatible, as mismatched updates can cause CAN message range errors

1. 1

   Turn on the ignition key

   Turn on the ignition key (engine off) and allow the AFS display to boot up completely.

2. 2

   Access the Vehicle Setup menu

   Access the Vehicle Setup menu on the display and locate the Tire Configuration page.

3. 3

   Correct the Tire Circumference value

   Input the exact rolling circumference of the tractor's tires (usually in millimeters or inches, depending on regional settings). Ensure the value falls within the acceptable parameters for your specific tractor model's transmission software.

4. 4

   Save the configuration and perform a key cycle

   Save the configuration and perform a key cycle (turn the ignition off, wait 30–60 seconds for the modules to power down completely, then turn it back on).

5. 5

   Clear the fault code

   Clear the fault code using the display's diagnostic menu or the CNH Electronic Service Tool (EST).

6. 6

   Test drive the tractor

   Test drive the tractor to ensure the ZDC calculates ground speed correctly and the code does not return.

7. 7

   Reflash Modules

   If the correct value is entered but the code immediately returns, use the CNH EST to reflash the firmware on both the AFS Display and the ZDC module to resolve any software corruption.