Case IH F-4207-09 - ECU – Engine Control Unit (ECU): CAN communication failure between vehicle controller and ECU controller - TSC1_VE message

The Engine Control Unit (ECU) failed to receive the TSC1_VE (Torque/Speed Control 1 - Vehicle to Engine) CAN bus message from the Vehicle Control Module (VCM) within a specific timeout window.

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect series (e.g., Magnum 400)
• Case IH 240 Series Combines
• Case IH Steiger series

1. 1

   Check for other active CAN faults to determine if the entire CAN bus is down or shorted.

2. 2

   Inspect the ECU and VCM connectors for moisture, corrosion, or backed-out pins.

3. 3

   Check ECU supply voltage by disconnecting the vehicle harness from the ECU and verifying proper voltage (12V or 24V) between the power supply pins and chassis ground with the key switch ON.

4. 4

   Check CAN bus resistance with the key switch OFF by disconnecting the harness at the ECU and measuring between CAN High and CAN Low (should be approximately 60 ohms; 120 ohms indicates a missing terminating resistor or open circuit).

5. 5

   Verify there is no continuity between the CAN pins and chassis ground to rule out a short to ground.

1. 1

   Disconnect battery

   Always disconnect the machine's battery power before servicing the CAN electrical system.

2. 2

   Repair CAN harness

   If diagnostic checks reveal an open or shorted CAN wire, trace the twisted-pair CAN harness between the VCM and the ECU. Repair any chafed, broken, or melted wires using OEM-approved splicing methods.

3. 3

   Perform connector maintenance

   If connector pins are corroded, clean them thoroughly with electrical contact cleaner and apply dielectric grease. Replace any damaged pins or connector housings.

4. 4

   Reassemble and power up

   Reconnect all harnesses and restore battery power.

5. 5

   Clear fault codes

   Turn the ignition ON and use the CNH Electronic Service Tool (EST) to clear the inactive fault codes.

6. 6

   Test operation

   Run the machine to verify the TSC1_VE message is being successfully received and the code does not return.

7. 7

   Replace faulty module

   If the wiring, terminating resistors, and voltages are perfectly intact but the fault persists, the ECU or VCM may have an internal hardware failure. Replace the faulty module and have it flashed/reprogrammed by a dealer.