Fendt 1.2.80 – A051 - ECU, engine control unit (EDC 7): Short circuit or break in wiring to injector valve 5

The engine control unit has detected an open circuit (broken wire/disconnected plug) or a short circuit (wiring touching ground or another voltage source) on the electrical circuit that controls the fuel injector for cylinder number 5.

• 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

   Inspect the wiring harness running from the EDC 7 ECU (A051) to Injector Valve 5 (Y100) for chafed wires, melted insulation, or physical breaks.

2. 2

   Disconnect the plug at Injector 5 and 'Connector A' at the EDC 7 ECU to check for bent pins, corrosion, or fluid intrusion (oil/water).

3. 3

   Using a multimeter, measure the continuity of the wires between the ECU connector and the injector plug, and check for continuity to ground to rule out a short circuit.

4. 4

   Measure the resistance across the pins of Injector 5 to determine if the injector solenoid is internally open or shorted.

1. 1

   Preparation

   Turn off the tractor ignition and disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Access Components

   Remove the necessary engine covers to access the fuel rail, injectors, and the EDC 7 ECU (A051).

3. 3

   Address Wiring Issues

   If the diagnostic checks revealed a broken or shorted wire, repair the damaged section of the harness using proper weatherproof splices, or replace the injector wiring harness entirely.

4. 4

   Replace Injector

   If the wiring tests good but the injector solenoid is internally shorted/open, remove the high-pressure fuel line and retaining clamp for Injector 5. Extract the injector, clean the injector bore, and install a new injector with a new copper sealing washer.

5. 5

   Reassembly

   Reconnect the injector harness and the EDC 7 ECU connectors. Reconnect the battery.

6. 6

   Clear Fault Codes

   Connect a diagnostic laptop and use SERDIA (Deutz engine diagnostic software) or FENDIAS to delete the error code from the A051 ECU memory.