New Holland 115 – ECM: Engine Speed or Cam Sensor Failed

The Engine Control Module (ECM) has lost the signal from either the engine speed sensor (crankshaft position sensor) on 8.3L and 9.0L engines, or the camshaft position sensor on 15L engines. These sensors provide critical rotational speed and position data required for the ECM to control fuel injection and spark timing. A loss of this signal typically results in the engine cranking but failing to start, or shutting down if it is already running.

• T8.xxx Series Tractors
• T4
• T5
• T7
• Boomer series
• TL70
• TL80
• TL90

1. 1

   Verify that fault code ENG 115 is active using the onboard diagnostic system

2. 2

   Check the battery voltage and ensure all main power and ground connections to the chassis and ECM are clean and tight

3. 3

   Visually inspect the wiring harness and connectors for the crankshaft or camshaft sensor for chafing, corrosion, rodent damage, and ensure the connector is securely latched

4. 4

   Check for inadvertently reversed connectors if both a crankshaft and camshaft position sensor are present on the engine

5. 5

   Perform a sensor resistance test using a multimeter (e.g., some engine speed sensors should read between 600 and 1800 ohms, verify with specific service manual)

1. 1

   Disconnect battery

   Disconnect the negative battery terminal before beginning any work on electrical components to prevent short circuits or damage to the ECU.

2. 2

   Locate the faulty sensor

   For 8.3L/9.0L engines, locate the engine speed (crankshaft) sensor on the flywheel housing, engine block, or transmission front case. For 15L engines, locate the cam sensor on the cylinder head, near the valve/timing cover, or on the fuel pump module (Cummins CAPS).

3. 3

   Remove the old sensor

   Disconnect the electrical connector, remove the single mounting bolt, and gently twist and pull the sensor to remove it from its bore.

4. 4

   Install the new sensor

   Compare the new sensor to the old one. Lubricate the O-ring on the new sensor with clean engine oil. Insert it into the bore with a twisting motion until fully seated. Install the mounting bolt and torque to 24 N·m (18 ft. lbs.).

5. 5

   Finalize repair

   Reconnect the electrical connector and negative battery terminal. Clear active fault codes using a diagnostic tool, then start the engine and let it idle for at least one minute to verify the repair.