Case IH 3314 – Engine Controller (EDC - Electronic Diesel Control / Engine ECU): Cylinder 6 Specific Errors - Signal Not Plausible

The engine control module has detected an electrical anomaly in the circuit for the fuel injector on cylinder #6. The electrical characteristics (resistance, voltage, or current draw) of the injector solenoid or its wiring harness do not match the expected parameters, or the injector is failing to respond correctly to the firing command.

• Magnum 235
• Magnum 250
• Magnum 260
• Magnum 280
• Magnum 290
• Magnum 310
• Magnum 340
• Magnum 370
• Magnum 380
• Steiger 350
• Steiger 435
• Quadtrac 370
• 7130
• 7230
• T8.275
• T8.360
• T8.390
• T8.410
• T8.435
• T9.390

1. 1

   Visual Inspection: Inspect the wiring harness and the specific connector at the Cylinder 6 injector for corrosion, loose pins, melted plastic, or chafing.

2. 2

   Electrical Testing (DVOM): Use a Digital Volt-Ohm Meter to check the resistance of the Cylinder 6 injector solenoid. Compare it to a known good cylinder (e.g., Cylinder 5).

3. 3

   Continuity & Short Testing: Check the continuity of the wiring harness from the Engine ECU to the injector. Test for short circuits to ground or short circuits to battery voltage within the harness.

4. 4

   Software Diagnostics: If available, use a diagnostic scan tool (like the Case IH EST or Jaltest) to perform a cylinder contribution test or an injector cut-out test to verify if the injector is firing mechanically.

1. 1

   Prep

   Disconnect the machine's battery to ensure electrical safety. Clean the area around the valve cover to prevent debris from entering the engine.

2. 2

   Access

   Remove the engine valve cover / rocker cover to access the fuel injectors on the FPT engine.

3. 3

   Disconnect

   Unplug the electrical connector from the Cylinder 6 fuel injector.

4. 4

   Remove Fuel Lines

   Loosen and remove the high-pressure fuel line (transfer tube) connected to the injector. Cap the fuel rail fittings to prevent contamination.

5. 5

   Extract Injector

   Remove the injector hold-down clamp/bolt. Carefully extract the injector from the cylinder head.

6. 6

   Clean

   Thoroughly clean the injector bore in the cylinder head, ensuring no old copper washer material or carbon buildup is left behind.

7. 7

   Install

   Install the new injector. Crucial: You must use new O-rings and a new copper sealing washer (gasket) on the tip.

8. 8

   Reassemble

   Reinstall the hold-down clamp and torque the bolt to exact OEM specifications. Reinstall the high-pressure fuel transfer tube.

9. 9

   Reconnect

   Plug the electrical connector back into the injector solenoid. Reinstall the valve cover with a new gasket if necessary.

10. 10

    Finalize

    Reconnect the battery. Prime the fuel system to remove air. Use a diagnostic tool to clear the 3314 fault code, run the engine, check for fuel leaks, and verify the code does not return. (Note: Depending on the exact ECU software, the new injector's trim code/IQA code may need to be programmed into the Engine ECU using a diagnostic tool).