New Holland 119-02 – ECU: Erratic Crankshaft Speed Signal Failure

The engine control system has detected that the crankshaft speed signal is erratic, intermittent, or incorrect. The Engine Control Unit (ECU) relies on the crankshaft position sensor (CKP) to monitor the rotational speed and precise position of the engine's crankshaft. This data is essential for accurately controlling fuel injection and ignition timing. When the signal becomes unreliable, the ECU loses synchronization, which can lead to engine performance issues such as failure to start, sudden stalling, rough running, and reduced power.

• T6.120
• T6.140
• T6.145
• T6.155
• T6.160
• T6.165
• T6.175
• T6.180
• T7.165
• T7.170
• T7.175
• T7.190
• T7.210
• T7.220
• T7.225
• T7.230
• T7.245
• T7.250
• T7.260
• T7.270
• T6030
• T6050
• T6070
• T6080
• T6090
• T7030
• T7040
• T7050
• T7060
• TM125
• T8.275
• T8.300
• T8.330
• T8.390
• T9030
• T9040
• T9050
• CX5.80
• CX5.90
• CX6.80
• CX6.90
• CX7080
• CX8080
• CX8.80
• CX8.90
• CR7.90
• CR8.90
• CR9060
• CR9070
• CR8080
• W130B
• W170B
• W130C
• W170C
• W190C

1. 1

   Inspect the crankshaft position sensor for physical damage, cracks, corrosion, or accumulated metallic debris.

2. 2

   Examine the sensor wiring harness and connector for fraying, cuts, melting, corrosion on the pins, and ensure the connector is securely latched.

3. 3

   Verify the sensor is mounted securely and check the air gap between the sensor and the reluctor wheel (standard clearance is typically 0.8mm to 1.0mm).

4. 4

   Connect a diagnostic scan tool, check for any other active or stored fault codes, and monitor 'Engine RPM' while cranking. A healthy signal should show a steady 100-500 RPM; a reading of zero or an erratic reading points to a circuit problem.

5. 5

   Identify if the sensor is an inductive (2-wire) or Hall-effect (3-wire) type. For an inductive sensor, perform a resistance test on the disconnected sensor using a multimeter. Inductive sensors typically read between 200 and 1,000 ohms (FPT NEF engines specify approximately 900 ohms). A reading of zero indicates a short, while O.L. indicates an open circuit.

6. 6

   Perform an AC voltage output test by back-probing the signal and ground wires with the sensor connected. While cranking, a functional sensor should generate a fluctuating AC voltage between 0.5V and 1.5V.

1. 1

   Disconnect power

   Turn off the engine and engage the master battery disconnect switch or disconnect the negative battery terminal for safety.

2. 2

   Access the sensor

   Remove any guards, panels, or other components necessary to gain access to the crankshaft position sensor, which is typically mounted on the engine block or flywheel housing.

3. 3

   Remove the old sensor

   Carefully press the release tab and unplug the electrical connector. Remove the single mounting bolt securing the sensor. Gently twist and pull the sensor straight out of its mounting hole. Do not pry it out with a screwdriver to avoid damaging the mounting surface.

4. 4

   Install the new sensor

   Clean the mounting surface. Apply a light coat of clean engine oil to the new sensor's O-ring and gently slide it into the mounting hole until fully seated. Install the mounting bolt by hand, then tighten to the manufacturer's specified torque. Securely plug in the electrical connector until it clicks.

5. 5

   Verify repair

   Reinstall any removed components and reconnect the battery. Start the engine to verify it runs smoothly. Use a diagnostic tool to clear the fault code from the ECU, check for any new codes, and operate the machine to ensure the issue is resolved.