Case IH 3067 – Engine Control Module (ECM): Cylinder 5 - Injector Cable Short circuit (High Side to Ground)

The engine control system has detected an electrical short circuit on the wiring circuit that supplies voltage to the fuel injector on cylinder number 5. This can be caused by a damaged wiring harness shorting against the engine block/chassis, wires shorting to each other, or an internal short circuit within the injector solenoid itself.

• Steiger T4B
• Magnum 235
• Magnum 260
• Magnum 290
• Magnum 315
• Magnum 340
• Magnum 370 (Series 4)
• Steiger 350-600 HP
• Farmall
• Maxxum
• Puma
• Optum
• 521D
• 621D
• Excavators

1. 1

   Visual Inspection: Inspect the engine wiring harness routing from the ECM to the cylinder 5 injector. Look closely for rubbed-through insulation, melted wires, or pinch points where the harness contacts metal brackets or hot engine components.

2. 2

   Isolate the Short: Disconnect the electrical connector at the cylinder 5 injector.

3. 3

   Test the Injector (Internal short cause): Using a digital multimeter, measure the resistance across the pins of the cylinder 5 injector solenoid. If the resistance is out of specification (reading as a dead short), the injector itself has failed internally.

4. 4

   Test the Harness (Wiring short cause): With the injector disconnected and the ECM disconnected, check the high-side wire of the cylinder 5 circuit for continuity to ground. If continuity to ground is present, the wiring harness is compromised.

5. 5

   Connector Check: Inspect the injector pigtail connector and the ECM pins for corrosion, water ingress, or bent pins that could bridge the circuit.

1. 1

   Power Down

   Turn off the machine and disconnect the battery ground cable to prevent accidental arcing or further damage to the ECM.

2. 2

   Access the Injector

   Remove any engine covers or valve covers necessary to access the cylinder 5 fuel injector and its wiring.

3. 3

   Address the Wiring

   If the diagnostic tests proved the harness is shorted, locate the damaged section. Repair the wire using OEM-approved splicing techniques (solder and marine-grade heat shrink) or replace the affected injector harness section/pigtail. Reroute the harness slightly or add protective loom to prevent future chafing.

4. 4

   Replace the Injector

   If the solenoid is internally shorted, clean the area around the injector, disconnect the high-pressure fuel line (cap the rail and line immediately), remove the hold-down clamp, and carefully extract the injector. Install the new injector with a new copper sealing washer and O-rings. Torque the hold-down clamp and high-pressure fuel lines to exact OEM specifications.

5. 5

   Reassembly

   Reconnect the injector electrical connector, reinstall covers, and reconnect the battery.

6. 6

   Clear Codes & Test

   Connect a diagnostic tool (like the CNH EASy tool or via the AFS Pro display) to clear the inactive 3067 fault code. Start the engine, check for fuel leaks, and verify that the engine runs smoothly without the code returning.