Fendt 1.2.81 – A051 - ECU, engine control unit (EDC 7): Short circuit or break in wiring to injector valve 6

In the context of the EDC 7 engine control system, fault code 1.2.81 indicates a short circuit or break in wiring to injector valve 6. The internal SERDIA (Deutz engine diagnostics program) fault codes associated with this error are FC:00A9 and FC:00AA.

• 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 A051 (EDC 7) control unit to injector valve 6 for physical breaks, chafing, or melted insulation that could cause a short circuit to the battery or ground.

2. 2

   Disconnect the injector harness and measure the resistance of injector valve 6 across its pins (should measure approximately 0.5 ohms).

3. 3

   If the engine can run, check the signal current at the separation point on the injection valve (e.g., testing pins at X1672) while the engine is without load to verify the EDC is sending the correct voltage.

1. 1

   Disconnect Power

   Disconnect the tractor's battery before beginning electrical repairs on the EDC system.

2. 2

   Harness Repair

   If the diagnostic checks reveal a broken wire or short in the harness between the A051 ECU and injector 6, repair the damaged section of the wiring loom or replace the injector harness segment.

3. 3

   Injector Replacement

   If the wiring tests perfectly but the injector solenoid fails the resistance test (open circuit or internal short), injector valve 6 must be replaced.

4. 4

   Sleeve/Seal Replacement

   When replacing the injector, it is highly recommended to replace the injector sleeve and the corresponding copper sealing rings to prevent coolant or compression leaks.

5. 5

   Clear Codes

   Reconnect the battery and use the SERDIA diagnostic software tool to delete the error codes (FC:00A9, 00AA) from the A051 ECU.

6. 6

   Test Run

   Start the tractor and verify that the engine runs smoothly on all cylinders without throwing the 1.2.81 code again.