Case IH 298967-12 - VCM – VCM: CAN bus: Internal CAN Rx buffer overflow

The fault is triggered when there is an excessive number of CAN messages intended for the steering controller, causing its internal receive (Rx) buffer to overflow. This is categorized as a severe hardware/communication fault, and the system will disable the electrohydraulic steering solenoids for safety.

• MAGNUM AFS Connect
• MX Magnum Series
• Steiger Series
• Patriot Sprayers (3330, 3340, 4420)

1. 1

   Reboot the machine to see if CAN control is restored, as this specific error is permanent until power is cycled

2. 2

   Check the PVED-CLS steering controller diagnostic LED (Blinking Orange/Green indicates bootloader mode; Solid Orange indicates initializing or on-road mode)

3. 3

   Measure resistance across CAN High and CAN Low with the battery disconnected (should be approximately 60 ohms) to ensure proper network termination

4. 4

   Inspect CAN bus wires leading to the steering valve for short circuits or wire breakage

5. 5

   Disconnect any recently installed aftermarket CAN devices (displays, third-party GPS, or telematics) to isolate potential network flooding or address conflicts

1. 1

   Turn off the engine and disconnect the negative battery cable.

2. 2

   Inspect the wiring harness connector at the PVED-CLS steering valve.

   Check for spread pins, corrosion, or moisture ingress. Clean and secure the connection.

3. 3

   Reconnect the battery and power on the machine.

   If the fault code clears and does not return, the issue was a temporary network disturbance or loose connection.

4. 4

   Replace the PVED controller if the fault code immediately returns or increments by 1 upon reboot.

   The internal hardware of the PVED controller has failed and the unit must be replaced.

5. 5

   Remove the retaining bolts securing the PVED-CLS actuator to the hydraulic steering valve block.

6. 6

   Install the new PVED-CLS controller.

7. 7

   Perform a steering calibration / AutoSteer calibration.

   Use the Case IH AFS Pro display or the dealer Electronic Service Tool (EST), as the new module must learn the mechanical spool compensation values.