Fendt 1E.1.B6 – A051 - Engine Control Unit (ECU) / Bosch EDC 7: A051 - ECU, engine control unit (EDC 7) - CAN message missing

Communication failure on the tractor's Controller Area Network (CAN) bus. The expected switch output messages from the engine control unit are not being broadcast or received by the rest of the tractor's network.

• 309 Vario COM III
• 310 Vario COM III
• 311 Vario COM III
• 312 Vario COM III
• 922 Vario COM III
• 924 Vario COM III
• 927 Vario COM III
• 930 Vario COM III
• 933 Vario COM III
• 936 Vario COM III
• 300 Vario COM III (309, 310, 311, 312)
• 400 Vario COM III (409, 410, 411, 412)
• 700 Vario COM III (711, 712, 714, 716)
• 800 Vario COM III (815, 817, 818)
• 900 Vario COM III (916, 920, 924, 926, 930, 936)

1. 1

   Read and Clear Codes: Connect the FENDIAS or SERDIA diagnostic tool (internal failure code FC:0075). Attempt to clear the fault to determine if it is an active hard fault or an intermittent glitch.

2. 2

   Check the CAN Bus Wiring: Inspect the CAN High and CAN Low lines between the A051 Engine ECU and the A002 Enhanced Control ECU / A050 Basic Control Unit.

3. 3

   Inspect the EDC7 Connectors: Check the 89-way harness connector at the Bosch EDC7 unit for water ingress, corrosion, or bent pins.

4. 4

   Verify Power and Ground: Ensure the EDC7 module is receiving stable voltage and has a clean ground connection.

1. 1

   Isolate the Wiring

   If the fault is active, use a multimeter to test the CAN bus resistance at the EDC7 connector (with the battery disconnected). It should read approximately 60 ohms. If it reads 120 ohms or open, there is a wiring break in the harness.

2. 2

   Repair Harness

   Repair any chafed wires or replace corroded connector pins at the ECU if applicable.

3. 3

   Replace/Clone the ECU

   If the wiring, power, and ground are all intact but the module still fails to communicate, the Bosch EDC7 unit has likely suffered an internal hardware failure and must be replaced.

4. 4

   Programming

   The replacement unit must undergo EOL (End of Line) programming to write the correct engine data record and immobilizer data for your specific chassis number. Alternatively, the original data can be cloned to a donor EDC7 unit using a bench tool (like K-TAG).

5. 5

   Clear Faults

   After repairing the wiring or replacing the ECU, use the SERDIA diagnostic software to delete the error (FC:0075) and verify that the CAN messages have returned.