Fendt 1.2.BD – A051 - ECU, engine control unit (EDC 7): CAN-message missing

The engine control unit is failing to receive expected communication data packets over the tractor's Controller Area Network (CAN bus) from other modules on the network.

• 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 (309, 310, 311, 312)
• Fendt 400 Vario COM III (411, 412)
• Fendt 700 Vario COM III (711, 712, 714, 716)
• Fendt 800 Vario COM III (815, 817, 818)
• Fendt 900 Vario COM III (916, 920, 924, 926, 930, 936)

1. 1

   Check for accompanying codes (such as 1.1.A1 or 1.1.B0) which indicate a broader communication failure between the A002 (enhanced control ECU) or A050 (basic control unit) and the A051 engine ECU.

2. 2

   Consult Fendt wiring diagram Sheet 36, which specifically covers the CAN bus routing for the A051 EDC 7 module.

3. 3

   Inspect the main harness separation points (connectors X1466, X1671, and X1672) at the A051 ECU for moisture, corrosion, or backed-out pins.

4. 4

   Measure the resistance and voltage of the CAN bus lines at the ECU connector to ensure the wiring harness is intact and not shorted to ground or power.

1. 1

   Disconnect Power

   Turn off the ignition and disconnect the battery before working on the ECU wiring.

2. 2

   Access the ECU

   Remove the battery case or right-hand side paneling to access the A051 Engine Control Unit.

3. 3

   Harness Repair

   If diagnostic testing revealed a break or short in the CAN bus wiring (Sheet 36), repair the damaged wires or replace the affected harness section. Clean any corroded connector pins with electrical contact cleaner.

4. 4

   ECU Replacement/Repair

   If the wiring harness tests perfectly, the CAN transceiver inside the Bosch EDC 7 unit may have failed. The ECU will need to be sent out for board-level repair or replaced entirely.

5. 5

   Clear the Fault

   Reconnect the system. Because this is a 1.2.XX series error, it must be manually deleted directly in the engine control unit using the SERDIA diagnostic software (clearing FC:007D) after the physical correction is made.

6. 6

   EOL Programming

   If a new or remanufactured ECU was installed, you must perform EOL (End of Line) programming to write the correct engine data record and tractor configuration to the new module.