Case IH 3078 – Engine Control Unit (ECU): Cylinder2 -Application Dependent

Electrical fault (short circuit, low voltage source, or signal failure) on the fuel injector circuit for engine cylinder number 2.

• Case IH Magnum 235 - 340 (Series 4)
• Case IH Steiger tractors
• Case 721F, 821F, and 921F Wheel Loaders

1. 1

   Check the wiring harness connecting the Engine ECU to the Cylinder 2 injector for short circuits to ground, battery, or an external source

2. 2

   Test the Cylinder 2 injector to determine if it has a defective or shorted internal coil

3. 3

   Verify the injection signals coming from the Engine ECU

4. 4

   Evaluate the Engine ECU for internal defects if wiring and injector tests pass

1. 1

   Halt Operation

   Stop the machine and turn off the engine to prevent further damage.

2. 2

   Inspect and Repair Wiring

   Trace the injector cable for Cylinder 2. If a short circuit or damaged wiring is found, repair or replace the wiring harness.

3. 3

   Replace the Injector

   If the wiring is intact but the injector coil tests out of specification (defective coil), replace the Cylinder 2 fuel injector.

4. 4

   Replace the ECU

   If both the wiring and the injector are functioning correctly but the low signal persists, the Engine ECU has an internal defect and must be replaced.

5. 5

   Clear Codes

   Use the CNH EASY diagnostic tool (or an equivalent Electronic Service Tool) to retrieve, verify, and clear the DTC fault codes after the repair is complete.