Case IH 3067 (DTC 6726) - ECU – Engine Control Unit (ECU A-095): Short circuit error of injector in cylinder 4

The system detects hardware errors in the injectors and their respective power stages. During the evaluation of the cylinder 4 injector (Y-064), the system detects a pattern indicating a short circuit.

• MAXXUM T4E
• 240 Series Axial-Flow Combines (7240, 8240, 9240)
• Case IH Magnum series (MX210, MX230, MX255, MX285)
• Case IH Puma series
• A8000 Sugar Cane Harvester
• A8800 Sugar Cane Harvester

1. 1

   Check for related injector faults (3083/DTC 6326 or 3075/DTC 6526) and resolve them first if present

2. 2

   Check for bank failures (3218/DTC 7216), as all injectors on the same bank can be affected by a single short

3. 3

   Verify that the tractor battery power supply has not been connected to an external power supply (like a jump box or external charger)

4. 4

   Test the engine wiring harness for continuity to ground or power to confirm if the short circuit is in the wiring rather than the injector itself

1. 1

   Disconnect External Power

   If an external power supply or charger is connected to the machine, remove it and cycle the key to see if the code clears.

2. 2

   Inspect the Wiring Harness

   Visually inspect the harness routing to the cylinder 4 injector (Y-064) for chafing, melted insulation, or pinched wires.

3. 3

   Test the Circuit

   Disconnect the cylinder 4 injector and the ECU A-095 connector. Use a multimeter to check for a short circuit to ground or a short circuit to voltage on the injector signal wires.

4. 4

   Repair/Replace Harness

   If a short circuit is indicated in the wiring, repair or replace the engine wire harness as required.

5. 5

   Replace the Injector

   If the wiring harness tests good, the short circuit is internal to the cylinder 4 injector solenoid. Replace the cylinder 4 injector.

6. 6

   Clear Codes

   Reconnect all components, turn on the battery disconnect, and use the Case IH Electronic Service Tool (EST) to clear the fault codes and verify the repair.