Case IH 3072 – Engine Control Module (ECM): Cylinder 6 - Unclassifiable Error in Injector

An electrical or operational anomaly in the fuel injector circuit for cylinder number 6 that the system cannot specifically classify as a standard open circuit or short circuit.

• Magnum 235-340 Series 4
• Steiger 350-600
• Puma
• Maxxum
• Axial-Flow Combine 7230
• Axial-Flow Combine 8230
• Axial-Flow Combine 9230
• Harvester A8000
• Harvester A8800

1. 1

   Inspect the fuel injector 6 connector and the engine controller (ECM) connector for secure connection, damage, and tight pins

2. 2

   Verify the correct tightening torque (1.5 Nm) for the flylead fixing nuts on the fuel injector solenoids

3. 3

   Disconnect the fuel injector solenoid flylead terminals for cylinder 6 and measure resistance (should be approximately 0.23 Ohms at 20°C)

4. 4

   Disconnect the engine ECU connector and test the specific injector pins on the harness side against a ground source to check for a short to ground

5. 5

   Turn the key switch ON and test the specific injector pins on the harness side against ground to check for a short to voltage

6. 6

   Verify the ECM has the correct software level if the injector and harness test fine

1. 1

   Disconnect battery

   Disconnect the battery to ensure safety while working on the engine's electrical system.

2. 2

   Access cylinder 6 injector

   If the diagnostic resistance test failed, access the cylinder 6 injector (this may require removing the valve cover depending on the specific FPT engine model).

3. 3

   Disconnect and cap lines

   Disconnect the electrical connector and the high-pressure fuel line to the cylinder 6 injector. Cap the fuel lines immediately to prevent contamination.

4. 4

   Remove faulty injector

   Remove the injector hold-down clamp/bolt and extract the faulty injector.

5. 5

   Clean injector bore

   Clean the injector bore thoroughly.

6. 6

   Install new injector

   Install the new injector with new O-rings and a new copper sealing washer. Note: Due to differences in oil output and atomization, it is highly recommended not to mix genuine and aftermarket injectors; replacing the full set is sometimes advised if using aftermarket parts.

7. 7

   Reinstall clamp and reconnect

   Reinstall the hold-down clamp and torque to OEM specifications. Reconnect the high-pressure fuel line and electrical connector.

8. 8

   Repair or replace harness

   If the harness was found to be faulty during diagnostics, repair the damaged wire or replace the injector wiring harness.

9. 9

   Finalize repair

   Reconnect the battery, bleed the fuel system of air, and clear the fault codes using a diagnostic scan tool. Run the engine to verify the repair.