Case IH 349 – ENG (Engine Controller / Engine ECU): Measured Speed is too high.

The engine controller is receiving a speed signal (typically from the engine speed/position sensor) that exceeds plausible operating limits. This is often caused by electrical noise, a failing sensor, or a short circuit in the sensor wiring that creates erratic, high-frequency signals.

• MX Magnum
• STX Steiger
• Case IH Magnum series
• Case IH Steiger series
• Case IH Puma series

1. 1

   Inspect the engine speed sensor (crankshaft/camshaft position sensor) and Engine ECU connectors for physical damage, corrosion, moisture, or pushed-back pins

2. 2

   Inspect the wiring harness between the speed sensor and the ECM for chafing, shorts to ground, or open circuits

3. 3

   Measure the resistance of the engine speed sensor to verify it falls within the OEM specification

4. 4

   Remove the sensor and check the magnetic tip for metal shavings or debris, which can distort the magnetic field and cause erratic high-speed readings

1. 1

   Turn off the key switch and disconnect the battery to prevent electrical damage.

2. 2

   Locate the engine speed sensor.

   Typically mounted on the flywheel housing or near the timing gear/camshaft, depending on the specific engine model.

3. 3

   Disconnect the wiring harness connector from the sensor.

4. 4

   Remove the retaining bolt securing the sensor and carefully pull the sensor out of its bore.

5. 5

   Clean the mounting surface on the engine block/housing to ensure the new sensor sits flush.

6. 6

   Install the new engine speed sensor and tighten the retaining bolt to the OEM torque specification.

7. 7

   Reconnect the wiring harness, ensuring the connector clicks securely into place.

8. 8

   Reconnect the battery and turn the key switch to the ON position.

9. 9

   Connect a diagnostic tool (such as Case IH EST or Cummins INSITE) to clear the inactive fault codes.

10. 10

    Start the engine and let it idle for 1 minute to verify that Fault Code 349 remains inactive.