Case IH 3071 – Engine Controller (Engine ECU / EDC - Electronic Diesel Control): Cylinder 3 - Injector Cable Short circuit (High Side to Ground)

The Engine Control Module has detected a short circuit to ground on the high side (the power supply side) of the electrical circuit for the cylinder 3 fuel injector. This condition prevents the injector from firing properly and is typically caused by a chafed wiring harness touching the engine block, a defective/internally shorted injector coil, or an internal failure within the ECU.

• Farmall
• skid steer
• Steiger T4B
• Magnum 235
• Magnum 250
• Magnum 260
• Magnum 280
• Magnum 290
• Magnum 315
• Magnum 340
• Magnum 380
• Steiger 350
• Steiger 370
• Puma 130
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• Puma 165
• Puma 185
• Puma 200
• Puma 225 CVX
• Maxxum series
• 580 Super N Backhoes
• Axial-Flow 5130
• Axial-Flow 6130
• Axial-Flow 7130
• Axial-Flow 7230
• Axial-Flow 8230
• Axial-Flow 9230

1. 1

   Inspect the wiring harness leading to the cylinder 3 injector. Look for chafing, melted insulation, or pinched wires where the harness routes near metal engine components or external sources.

2. 2

   Disconnect the electrical connector at the cylinder 3 injector. Use a multimeter to check the resistance of the injector coil to ground. If there is continuity to ground, the injector coil is defective and the injector must be replaced.

3. 3

   Check the wiring continuity and resistance from the Engine ECU connector to the injector connector to isolate a harness short.

4. 4

   If the wiring harness and the injector both test fine, check the injection signals. Depending on the pattern, the defect may be caused by internal ECU problems, which would require ECU replacement.

1. 1

   Turn off the machine, remove the key, and disconnect the battery to prevent electrical damage.

2. 2

   Locate the cylinder 3 fuel injector on the engine block and disconnect its electrical connector.

3. 3

   If the harness is faulty: Repair the damaged section of the wire or replace the engine injector wiring harness.

4. 4

   If the injector is faulty: Clean the area around the injector to prevent debris from entering the cylinder.

5. 5

   Remove the high-pressure fuel injection pipe/line connected to cylinder 3.

6. 6

   Remove the injector hold-down clamp/bolt and carefully extract the faulty cylinder 3 injector.

7. 7

   Clean the injector bore thoroughly. Install the new injector using new O-rings and a new copper sealing washer.

8. 8

   Reinstall the hold-down clamp and torque to OEM specifications.

9. 9

   Reinstall the high-pressure fuel line.

   Note: It is highly recommended to replace the high-pressure fuel pipe once it has been removed, as they are often single-use crush-fit items.

10. 10

    Reconnect the electrical connector to the injector.

11. 11

    Reconnect the battery, clear the fault codes from the Engine ECU using a diagnostic tool, and run the engine to verify the repair and check for fuel leaks.