Case IH F-641-14 - ECU – ECU: eVGT power supply electrical failure

The engine's control system has detected a loss of voltage, a short circuit, or an internal electrical failure within the Electronic Variable Geometry Turbocharger (eVGT) actuator circuit.

• MAGNUM AFS Connect
• Axial-Flow Combines (240 Series: 7240, 8240, 9240)
• Optum CVT Tractors (Optum 270, 300)
• Magnum AFS Connect Tractors
• Steiger Tractors

1. 1

   Check for accompanying CAN communication codes (such as 3598 or 641-31). If present, the issue is likely in the CAN bus wiring rather than the actuator itself.

2. 2

   Inspect the dedicated eVGT fuse (e.g., F-203 on Optum models) and the eVGT actuator relay.

3. 3

   Visually inspect the engine wiring harness between the ECU and the eVGT actuator for chafing, melted wires, or corrosion at the connector pins.

4. 4

   Perform a voltage test: Turn the ignition switch OFF and disconnect the harness from the eVGT actuator. Remove the eVGT actuator relay. Turn the ignition switch ON. Use a multimeter to check for voltage from the vehicle engine harness side of the eVGT actuator connector (typically pin 4) to chassis ground to verify power supply matches OEM specifications.

1. 1

   Turn off the ignition and disconnect the machine's battery.

2. 2

   If the diagnostic checks reveal a blown fuse (e.g., F-203), replace the fuse. If the wiring harness is damaged, repair the broken/shorted wires or replace the harness section.

3. 3

   If the wiring, fuses, and relays test good but the fault remains active, the eVGT actuator has suffered an internal electrical failure and must be replaced.

4. 4

   Disconnect the electrical connector from the eVGT actuator.

5. 5

   Unbolt and remove the defective eVGT actuator from the turbocharger assembly.

6. 6

   Install the new eVGT actuator and torque the mounting hardware to OEM specifications.

7. 7

   Reconnect the electrical harness to the actuator and reconnect the battery.

8. 8

   Connect the Case IH Electronic Service Tool (EST). Clear the inactive fault codes from the ECU.

9. 9

   Perform the eVGT actuator calibration/learn procedure via the EST to sync the new actuator's position with the ECU.