Case IH 3311 – Engine Control Unit (ECU): Cylinder 6 Specific Errors - No Signal

The engine control module is not detecting an electrical signal from the fuel injector solenoid on Cylinder 6. This indicates an open circuit, a disconnected wiring harness, or a completely failed injector solenoid coil.

• Magnum 235
• Magnum 250
• Magnum 260
• Magnum 280
• Magnum 290
• Magnum 315
• Magnum 340
• Magnum 350
• Magnum 370
• Magnum 380
• Steiger 350
• Steiger 370
• Quadtrac 350
• Quadtrac 370
• Puma
• Maxxum
• MX Series
• TG Series
• Axial-Flow 6130
• Axial-Flow 7130
• Axial-Flow 7230
• Axial-Flow 8240
• Patriot Series

1. 1

   Visually inspect the wiring harness and connectors between the Engine ECU and the Cylinder 6 fuel injector for chafed wires, melted insulation, or disconnected plugs

2. 2

   Disconnect the Cylinder 6 injector harness and the ECU connector to check for bent, pushed-out, or corroded pins

3. 3

   Measure the resistance across the pins of the Cylinder 6 injector solenoid. An infinite reading indicates an open circuit and internal injector failure

4. 4

   If the injector tests within specification, test the wiring harness for continuity from the injector plug back to the ECU to rule out a broken wire

1. 1

   Power Down

   Turn off the engine, remove the key, and disconnect the battery to prevent electrical shorts.

2. 2

   Access the Injector

   Remove the engine hood, side panels, and the engine valve cover (if the injectors are located under the cover on your specific FPT engine variant) to access the fuel rail and injector harness.

3. 3

   Repair Wiring

   If the diagnostic checks revealed a broken wire or damaged connector, repair the wiring harness or replace the specific engine injector harness section.

4. 4

   Replace Injector

   If the injector solenoid is open/dead: Disconnect the high-pressure fuel line from the Cylinder 6 injector and cap the rail fitting to prevent contamination. Remove the injector hold-down clamp/bolt. Carefully extract the Cylinder 6 fuel injector from the cylinder head. Clean the injector bore thoroughly. Install the new injector with new O-rings and a new copper crush washer. Reinstall the hold-down clamp and torque to OEM specifications. Reconnect the high-pressure fuel line and torque to spec.

5. 5

   Reassembly

   Reconnect the electrical harness to the injector. Reinstall the valve cover and any removed panels.

6. 6

   Clear Codes

   Reconnect the battery. Use a diagnostic tool (such as the CNH EST or Jaltest) to clear the 3311 fault code.

7. 7

   Test

   Prime the fuel system, start the engine, and check for leaks and proper operation.