New Holland ENG 3300 – Engine Control Unit (ECU): Cylinder 3 Specific Errors - Signal Low

The engine control system has detected that the electrical signal to/from the fuel injector on cylinder 3 is abnormally low, or the injector is failing to respond mechanically to the electrical command.

• T6030
• T6050
• T6070
• T7 series
• T8.275
• T8.300
• T8.390
• CR9040
• CR9090
• CR10.90
• CX8080
• CX8090
• Magnum
• Puma
• Maxxum
• Axial-Flow

1. 1

   Inspect the wiring harness and connectors routing from the Engine ECU to the Cylinder 3 fuel injector. Look for chafing, breaks, or short circuits to ground.

2. 2

   Verify that all connectors to the ECU and the injector are not damaged and are properly seated. Ensure the connector locks are not broken; replace the connector pigtails if the locks fail to hold securely.

3. 3

   Measure the resistance of the Cylinder 3 injector solenoid to check for an internal short or open circuit.

4. 4

   Use the CNH EST to check the CAN network, monitor rail pressure deviations, and verify if the fault is active or intermittent.

1. 1

   Disconnect battery

   Turn off the ignition and disconnect the battery to prevent electrical spikes.

2. 2

   Access harness area

   Gain access to the engine valve cover/injector harness area.

3. 3

   Disconnect connector

   Disconnect the electrical connector at the Cylinder 3 fuel injector.

4. 4

   Inspect pins

   Inspect the pins for corrosion, moisture, or bending. Clean and secure if necessary.

5. 5

   Repair wiring

   If damaged wiring is found during the diagnostic checks, repair or replace the damaged section of the harness and retest the circuit.

6. 6

   Determine injector replacement

   If the wiring and connectors are in good condition but the fault remains active (or if the injector fails the resistance test), the OEM manual dictates: "Cylinder 3 injector mechanical response fault (replace injector)."

7. 7

   Replace fuel injector

   Depressurize the fuel system and replace the Cylinder 3 fuel injector following standard OEM mechanical procedures (ensure the injector bore is clean and use new sealing washers/O-rings).

8. 8

   Clear codes and test

   Reconnect the battery, use the EST to clear the fault codes, and run the engine to confirm the elimination of the fault.