New Holland ENG 485 – Engine Control Module (ECM): Rear Fueling actuator overfueling

The Engine Control Module (ECM) has detected an unexpectedly high fuel flow (higher than desired) from the rear bank of the fuel system. This occurs if the actuator sticks open mechanically or is commanded open too long due to an electrical short. The ECM will immediately illuminate the red STOP ENGINE lamp, and the engine will either derate to idle-only mode or shut down completely.

• TG series tractors
• CR/CX series combines
• CR9090
• CX8080
• CX8090 Elevation
• FR forage harvesters

1. 1

   Check the ECM and the rear fueling actuator wiring harness for any shorts to ground, shorts to voltage, or open circuits.

2. 2

   Inspect the connector pins at the rear fueling actuator and the ECM for corrosion, moisture, or pushed-back pins.

3. 3

   Test the resistance of the rear fueling actuator coil to ensure it is not internally shorted or open.

4. 4

   Check the fuel filter/water separator for contamination (water or debris).

1. 1

   Safety First

   Turn off the key switch and disconnect the battery to prevent electrical shorts or accidental engine cranking.

2. 2

   Locate the Component

   Locate the rear fuel metering actuator on the fuel control housing (CAPS pump). It is the first actuator from the rear of the engine, located on the intake side of the engine below the exhaust gas mixer.

3. 3

   Disconnect Wiring

   Carefully unplug the wiring harness connector from the rear fueling actuator.

4. 4

   Harness Repair (If Applicable)

   If your diagnostic tests revealed a short or break in the wiring, repair or replace the injector/actuator harness.

5. 5

   Remove the Actuator

   If the harness is intact but the actuator is mechanically stuck open or electrically failed, remove the mounting hardware securing the actuator to the fuel control housing.

6. 6

   Clean and Prep

   Remove the faulty actuator and thoroughly clean the mounting surface on the pump housing, ensuring no dirt enters the fuel system.

7. 7

   Install New Part

   Install the new rear fueling actuator using new O-rings/seals. Torque the mounting bolts to OEM specifications.

8. 8

   Reassembly

   Reconnect the wiring harness and reconnect the battery.

9. 9

   Clear Codes and Test

   Use a diagnostic tool (such as the CNH Electronic Service Tool or Cummins INSITE) to clear the inactive fault codes. Start the engine and verify that the red STOP ENGINE lamp remains off and normal throttle response is restored.