Case IH F-102-15 - ECU – Engine Control Unit (ECU): Intake air pressure sensor: Plausibility Check for air pressure at the upstream of intake valve sensor

The Engine Control Unit (ECU) has detected that the intake air pressure (boost pressure) reading is implausible—specifically, the turbo boost pressure is reading higher than expected or does not align with the commanded parameters and other sensor readings (like barometric pressure).

• MAGNUM AFS Connect
• Case IH Magnum series (e.g., 235-340)
• Case IH Maxxum series
• Case IH Puma series
• Case IH Combines (e.g., 7010 series)

1. 1

   Perform a Key-On, Engine-Off (KOEO) test using a diagnostic tool to compare intake air pressure and barometric pressure readings (they should be nearly identical).

2. 2

   Inspect the wiring harness and connector at the intake air pressure sensor for chafed wires, corrosion, or shorts.

3. 3

   Remove the sensor and check the tip and mounting port for heavy soot buildup, debris, or physical damage.

4. 4

   Verify that the turbocharger wastegate or Variable Geometry Turbo (VGT) actuator is not mechanically stuck closed, causing an actual overboost condition.

1. 1

   Turn off the machine, remove the key, and allow the engine to cool.

2. 2

   Locate the intake air pressure (boost) sensor.

   It is typically mounted on the intake manifold, air box, or just above the oil filter, depending on the specific engine model.

3. 3

   Disconnect the electrical harness connector from the sensor.

4. 4

   Unbolt or unthread the sensor from its mounting port.

5. 5

   Clean the mounting port on the manifold.

   Ensure it is free of soot and debris so the new sensor can read accurately.

6. 6

   Install the new intake air pressure sensor.

   Ensure the rubber seal/O-ring is properly seated to prevent boost leaks.

7. 7

   Reconnect the electrical harness connector.

8. 8

   Connect a diagnostic tool, clear the F-102-15 / 3794 fault codes, and start the engine.

9. 9

   Monitor live pressure readings under load.

   Ensure the boost pressure is now within the expected OEM parameters.