Case IH F-518698-31 - ECU – Engine Control Unit (ECU): Exhaust flap actuator is over temperature

The 'smart' exhaust flap actuator has reported an internal overheating condition via the CAN bus network, typically caused by mechanical friction, an electrical supply problem, or excessive exhaust gas temperatures.

• MAGNUM AFS Connect
• 240 Series Axial-Flow Combines
• Austoft 9900 Sugarcane Harvesters
• Farmall (110A-140A)
• Vestrum (100-130)
• Maxxum (115-145)
• Optum
• Puma
• Steiger

1. 1

   Disconnect the actuator linkage and manually move the exhaust flap to check for physical binding, jamming, or heavy carbon buildup (mechanical friction cause).

2. 2

   Inspect the wiring harness and connector to the exhaust flap actuator for melted wires, corrosion, or shorts, and verify correct supply voltage (electrical supply cause).

3. 3

   Verify the CAN bus connection, ensuring the CAN controller is functioning correctly with no broken or disconnected cables.

4. 4

   Verify the engine is not running excessively hot due to a restricted DPF or cooling system failure, and check actuator coolant lines for blockages if applicable (excessive heat cause).

1. 1

   Cool Down

   Ensure the machine has been turned off and the exhaust system is completely cool to the touch.

2. 2

   Inspect and Clean

   Locate the exhaust flap valve assembly in the exhaust stream. If the flap is mechanically stuck, use a penetrating solvent/cleaner to dissolve carbon buildup and free the butterfly valve.

3. 3

   Test Actuator Movement

   If the flap moves freely but the actuator is still throwing the over-temperature code, the internal motor or circuitry of the actuator is likely fried from previous resistance or heat exposure.

4. 4

   Replace Actuator

   Disconnect the electrical harness (and coolant lines, if applicable to your specific engine model). Unbolt the actuator from the exhaust flap housing.

5. 5

   Install New Part

   Mount the new actuator, reconnect the linkage, and plug in the electrical connector.

6. 6

   Clear Codes

   Use the diagnostic service tool to clear the Level 2/3 error from the fault code memory and run the machine to verify the code does not return.