Case IH 19027 (F-518694-12) - ECU – Engine Control Module (ECM): Exhaust flap actuator supply voltage out of range

The control module has detected that the electrical supply voltage going to the electronic exhaust flap actuator (part of the exhaust brake and SCR thermal management system) is outside of the expected operating parameters.

• VESTRUM CVX
• Case IH 240 Series Axial-Flow Combines
• Case IH Vestrum Series Tractors (Vestrum 100, 110, 120, 130)
• Case IH Farmall Tractors (40, 45, 50 with Cab and CVT)
• Case IH Puma Series

1. 1

   Check for related fault codes (such as 19033, 19035, or 19026) which may indicate a mechanically seized flap rather than an isolated electrical failure.

2. 2

   Visually inspect the wiring harness leading to the exhaust flap actuator for melted wires, chafing against the exhaust pipe, or corrosion inside the connector.

3. 3

   Disconnect the actuator and use a multimeter to measure the supply voltage and ground at the harness connector with the key in the ON position. Ensure voltage matches system specification (12V or 24V) and is not dropping out.

4. 4

   With the actuator removed or disconnected, manually check the exhaust flap linkage to ensure it moves freely. A butterfly valve seized with soot or rust will cause the actuator to over-amp and fail.

1. 1

   Power Down

   Turn off the machine, remove the key, and disconnect the battery to prevent electrical shorts during repair.

2. 2

   Locate the Actuator

   Locate the exhaust flap actuator, which is mounted on the exhaust pipe assembly. Be prepared to clamp coolant lines if removing the entire valve assembly, as engine coolant often cools this actuator on NEF engines.

3. 3

   Disconnect Electrical and Linkage

   Unplug the electrical connector from the actuator.

4. 4

   Remove the Actuator

   Remove the mounting bolts securing the electronic actuator to the exhaust flap housing.

5. 5

   Clean and Inspect

   Clean the mounting surface. Verify once more that the mechanical flap inside the exhaust pipe moves freely. If it is seized, the entire exhaust brake valve assembly may need to be cleaned or replaced.

6. 6

   Install the New Part

   Mount the new exhaust flap actuator, ensuring the linkage aligns correctly with the flap mechanism. Torque the mounting bolts to OEM specifications.

7. 7

   Reconnect

   Plug the electrical connector back in and reconnect the battery.

8. 8

   Test and Clear Codes

   Turn the key to the ON position. The ECM will perform a power-up test (sweeping the exhaust flap). Clear the inactive 19027 fault code using a diagnostic tool and start the engine to verify the code does not return.