Case IH 3063 – Engine ECU: Cylinder 1 - Injector Cable Short circuit (High Side to Ground)

This fault code indicates that the engine control system has detected a short circuit to ground on the high-voltage side of the wiring circuit for the Cylinder 1 fuel injector.

• Farmall
• skid steer
• Steiger T4B
• Case IH Magnum 235 - 340 (Series 4)
• Case IH STX Steiger tractors (350 to 600 HP)
• Case IH Puma 165, 180, 195, 210, 225 CVX
• Case 580 Super N Tractor Loader Backhoes

1. 1

   Visually and electrically check the wiring harness between the Engine ECU and the Cylinder 1 fuel injector for chafing, rubbing, or exposed wires grounding out against the engine block or chassis

2. 2

   Test the resistance of the Cylinder 1 injector coil to determine if a defective internal coil is causing a high-side short to ground

3. 3

   Check the injection signals coming from the ECU to ensure the controller is outputting the correct voltage

4. 4

   If the wiring and injector both test perfectly fine, verify if the Engine ECU has an internal defect

1. 1

   Disconnect battery

   Disconnect the battery to ensure safety while working on the high-voltage injector circuits.

2. 2

   Repair or replace wiring harness

   If the diagnostic checks reveal damaged wiring, repair the affected section of the injector harness or replace the entire engine wiring harness.

3. 3

   Replace Cylinder 1 fuel injector

   If the wiring is intact but the Cylinder 1 injector coil is defective, remove the valve cover/components as necessary for your specific engine (e.g., FPT common rail) and replace the Cylinder 1 fuel injector. Ensure the copper sealing washer and rubber O-ring are properly in place and lubricated when installing the new injector.

4. 4

   Replace Engine ECU

   If both the wiring and the injector are confirmed good, the internal circuitry of the Engine ECU has failed. Replace the Engine ECU.

5. 5

   Clear fault codes and verify

   Reconnect the battery, clear the fault codes using an EST diagnostic tool, and run the engine to verify the code does not return.