Case IH F-103-11 - ECU – Engine Control Unit (ECU): Turbine over speed failure

The Engine Control Unit (ECU) has detected that the turbine speed of the electronic Variable Geometry Turbocharger (eVGT) has exceeded its maximum safe operating limit. This can be caused by a loss of control over the turbocharger vanes, electrical faults in the actuator circuit, or physical binding of the actuator/vanes. If a full power loss is experienced, the engine may automatically reduce to low idle speed to protect itself.

• MAGNUM AFS Connect
• Case IH 240 Series Axial-Flow Combines (7240, 8240, 9240)
• Case IH Steiger & Quadtrac Tractors (350, 400, 425, 450, 475, 500, 525, 550, 600)
• Case IH Magnum Tractors with eVGT setups

1. 1

   Check for Accompanying Codes: Use the Electronic Service Tool (EST) to check for related eVGT fault codes that might pinpoint the root cause, such as DTC 3598 / SPN 3858, DTC 3498 / SPN 3861, or DTC 8998 / SPN 3868.

2. 2

   Inspect the Wiring Harness: The ECU monitors the wiring harness between the actuator and the ECU. Check for faulty wiring, open circuits, or a short to voltage between the EVGT actuator relay (pin 87) and the EVGT actuator connector (pin 4).

3. 3

   Test the EVGT Actuator Relay: Use a multi-meter to check for continuity from pin 30 to pin 87 on the relay. There should be no continuity when unpowered.

4. 4

   Check Fuses: Verify the condition of the eVGT actuator fuse (e.g., F-203, 20A Mini Yellow fuse).

5. 5

   Mechanical Inspection: Inspect the turbocharger and actuator for physical damage, excessive carbon buildup, or binding of the variable vanes.

1. 1

   Disconnect Power

   Disconnect the machine's battery power before servicing the ECU, wiring harness, or eVGT actuator to prevent electrical shorts.

2. 2

   Repair Wiring/Relays

   If the diagnostic checks revealed a short to voltage or an open circuit, repair or replace the affected section of the wiring harness. If the relay failed the continuity test, replace the EVGT actuator relay.

3. 3

   Replace the eVGT Actuator

   If the wiring and relays are intact but the actuator is failing to initialize or control the vanes (causing the overspeed), remove the faulty eVGT actuator.

4. 4

   Install New Actuator and Gasket

   Install the replacement eVGT actuator. Always use a new VGT actuator gasket to prevent exhaust leaks and maintain actuator efficiency.

5. 5

   Reassemble and Reconnect

   Reconnect the actuator wiring harness and restore battery power.

6. 6

   Clear Codes and Test

   Connect the Electronic Service Tool (EST), clear the inactive fault codes, and run the engine under load to verify that the turbocharger operates within normal speed parameters and the code does not return.