Case IH F-518307-09 - ECU – Engine Control Unit (ECU / ECM): CAN communication failure regarding the TSC1_VR message

A CAN communication failure between the vehicle controller and the ECU controller specifically regarding the TSC1_VR message (Engine Brake selection). The fault triggers when the Engine Control Unit (ECU) receives an invalid value, experiences message corruption, or completely loses communication with the main machine/vehicle controller over the CAN bus network.

• MAGNUM AFS Connect
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• Case IH Magnum Series Tractors

1. 1

   Verify if any other related vehicle CAN faults exist and resolve broader network issues first

2. 2

   Check that the machine battery power supply has not been connected to an external power supply (like a jump box or external charger)

3. 3

   Disconnect the vehicle harness from the ECU (connector X-911) and check for proper supply voltage with the ignition ON

4. 4

   Test the twisted pair network to ensure the CAN termination resistance is correct (typically 60 ohms across the high and low pins with battery disconnected)

1. 1

   Isolate the Power

   Turn off the machine and disconnect any external power supplies or chargers.

2. 2

   Inspect the Harness

   Visually inspect the wiring harness running between the main vehicle/machine controller and the Engine ECU. Look for chafing, pinched wires, or corrosion at the connectors (specifically connector X-911 at the ECU).

3. 3

   Clean and Reconnect

   If corrosion or loose pins are found, clean the terminals with contact cleaner, ensure pins are seated tightly, and reconnect the harness.

4. 4

   Repair Wiring

   If the multimeter tests in the diagnostic phase reveal an open circuit or short to ground on the CAN High or CAN Low wires, splice and repair the damaged section of the twisted-pair wiring.

5. 5

   Clear and Retest

   Turn the ignition ON and clear the fault codes. Run the engine and engage the engine brake to verify if the TSC1_VR message is successfully transmitting.

6. 6

   Module Replacement

   If the wiring harness is fully intact, voltage is correct, and the CAN termination resistor inside the ECU is burnt out or failing, the ECU itself (or the vehicle controller) will need to be replaced and reprogrammed by a certified Case IH dealer.