Fendt 1.2.7A – A051 - ECU, engine control unit (EDC 7): Short circuit in cylinder bank 2 injector valves.

The engine control unit has detected an electrical short circuit in the wiring harness or the injector solenoids for the fuel injectors grouped into "bank 2". When this fault is active, the ECU initiates a "Cylinder switch-off" (disabling the affected cylinders) to protect the engine and electrical system, which will result in a severe loss of power and rough running.

• 411 Vario COM III
• 412 Vario COM III
• 413 Vario COM III
• 414 Vario COM III
• 415 Vario COM III
• 712 Vario COM III
• 714 Vario COM III
• 716 Vario COM III
• 718 Vario COM III
• 818 Vario COM III
• 820 Vario COM III
• FENDT 300 Vario (COM III)
• FENDT 400 Vario (COM III)
• FENDT 700 Vario (COM III)
• FENDT 800 Vario (COM III)
• FENDT 900 Vario (COM III)

1. 1

   Visually inspect the injector wiring harness leading from the A051 EDC 7 control unit to the cylinder head. Look for chafed insulation, melted wires, or pinch points that could cause a short to ground or short to voltage.

2. 2

   Disconnect the wiring harness from the injectors on bank 2. Measure the resistance across the terminals of each injector solenoid using a multimeter. A reading of near zero ohms indicates an internally shorted injector that must be replaced.

3. 3

   Inspect the main harness connectors at the EDC 7 ECU and the pass-through connectors at the cylinder head for oil intrusion, water ingress, or bent/corroded pins.

4. 4

   Connect the Fendt/Deutz SERDIA diagnostic tool to monitor the injector circuits and confirm the short is isolated to bank 2.

1. 1

   Disconnect Power

   Disconnect the tractor's battery to prevent further electrical damage to the EDC 7 module.

2. 2

   Gain Access

   Depending on the specific Deutz engine model (e.g., TCD 2012), remove the engine covers or valve cover to access the internal/external injector wiring harness and the injectors.

3. 3

   Replace the Faulty Component

   If the wiring harness is shorted (chafed or brittle), replace the injector wiring harness. If an injector failed the resistance test, remove the high-pressure fuel line, unbolt the injector hold-down clamp, and extract the shorted injector. Install a new injector with new copper sealing washers and O-rings.

4. 4

   Reassembly

   Reinstall the harness, torque the injector clamps and fuel lines to OEM specifications, and reinstall the valve cover/engine covers.

5. 5

   Clear Codes

   Reconnect the battery. You must use the SERDIA diagnostic software to delete the error (FC:009B) from the A051 ECU memory.

6. 6

   Test Run

   Start the tractor and verify that the cylinder switch-off condition has cleared and the engine runs smoothly.