CLAAS Id776Ah / 776Ah (656 05) – ENG (A15): Open circuit on the electronic injector of cylinder n°6

The Engine Control Unit has detected that the current to Injector #6 is less than expected, indicating a break in the circuit. The engine will run with difficulty, run rough, and misfire because the ignition/fuel delivery of the injector in cylinder n°6 is inoperative.

• Axion 810
• Axion 820
• Axion 830
• Axion 840
• Axion 850
• Arion 610
• Arion 630
• Arion 640
• Jaguar Harvesters

1. 1

   Visually inspect the wiring harness between the Engine ECU and Injector #6 for chafed wires, melted insulation, or disconnected/loose plugs.

2. 2

   Disconnect the plug at Injector #6 and the ECU to check for pushed-back pins, corrosion, or moisture inside the connectors.

3. 3

   Using a multimeter, test the wiring harness for continuity between the ECU pins and the injector connector, ensuring there is no short to ground or break in the wire.

4. 4

   Measure the resistance across the pins of Injector #6; an infinite resistance reading confirms an internal open circuit (failed injector solenoid).

5. 5

   If wiring tests fine, swap Injector #6 with an adjacent cylinder (e.g., Injector #5), clear codes, and run the engine. If the fault code changes to the new cylinder (e.g., 655 05 for cylinder 5), the injector is definitively the point of failure.

1. 1

   Preparation

   Turn off the machine, disconnect the battery, and thoroughly clean the area around cylinder #6 to prevent debris from entering the engine.

2. 2

   Removal

   Disconnect the electrical connector from Injector #6 (Y320-6). Loosen and remove the high-pressure fuel line connecting the common rail to the injector. Cap the rail fitting to prevent contamination. Remove the injector hold-down clamp/bolt and carefully extract the injector from the cylinder head.

3. 3

   Installation

   Clean the injector bore in the cylinder head. Install the new injector using a new copper sealing ring/washer (never reuse the old seal). Reinstall the hold-down clamp and torque the bolt to the OEM specification found in the engine repair manual. Reconnect the high-pressure fuel line and torque to spec. Reconnect the electrical harness.

4. 4

   Calibration & Bleeding

   Bleed the fuel system if required by the specific engine manual. Using the CLAAS METADIAG or CDS diagnostic tool, enter the new injector's QR code / calibration string into the Engine ECU (ENG A15). Clear the fault codes and test run the machine to verify the misfire is resolved.