Case IH 3090 – Engine Control Unit (ECU): Camshaft Speed Sensor Malfunction

The sensor generates signals from the magnetic flow lines of the camshaft timing gear, which the control unit uses to determine engine position and injection timing. A 'High Voltage,' 'Out of Range,' or 'No Signal' condition means the controller is not receiving a valid, stable reading to properly time the engine.

• skid steer
• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)
• Steiger Series Tractors
• Puma Series Tractors
• Maxxum Series Tractors
• Farmall Series Tractors

1. 1

   Check the wiring harness and connectors between the camshaft speed sensor and the Engine ECU for an electrical intermittent open, short circuit, or corrosion.

2. 2

   Verify that the sensor is mounted correctly. A loose sensor can alter the required air gap, leading to signal loss.

3. 3

   Use an Electronic Diagnostic Tool (EDT) to evaluate the raw signals and determine if the camshaft phase signal is stable.

4. 4

   Check the correct position and condition of the camshaft signal wheel (and crankshaft signal wheel) to ensure no physical damage is causing the signal loss.

1. 1

   Disconnect battery

   Disconnect the machine's battery to prevent electrical shorts during service.

2. 2

   Locate sensor

   Locate the camshaft speed sensor on the engine block (typically near the camshaft timing gear).

3. 3

   Disconnect connector

   Disconnect the electrical connector from the sensor.

4. 4

   Remove sensor

   Remove the retaining fastener(s) and carefully extract the sensor from its mounting bore.

5. 5

   Clean mounting surface

   Clean the mounting surface to ensure the new sensor seats perfectly flat. Note: Proper seating is critical to maintaining the correct air gap for the induction sensor.

6. 6

   Install new sensor

   Install the new camshaft speed sensor and tighten the retaining bolt to OEM torque specs.

7. 7

   Reconnect connector

   Reconnect the electrical connector.

8. 8

   Clear fault codes

   Reconnect the battery and use a diagnostic tool to clear the fault codes.

9. 9

   Verify repair

   Run the engine to verify the repair. Note: If the fault persists (e.g., Signal Above Range Max) and all wiring/sensors are confirmed good, the Engine Controller itself may need to be replaced.