Fendt B.1.43 – A002 - ECU, Enhanced Control: Error counter overflow between A004 Control console and Teach-in (program run)

CAN bus communication failure (data transfer fault) where the internal error counter has exceeded its limit while trying to communicate between the control console and the Teach-in program. The Variotronic TI (Teach-in / automated headland management) function will not operate.

• 409 Vario
• 410 Vario
• 411 Vario
• 412 Vario
• 711 Vario
• 712 Vario
• 714 Vario
• 715 Vario
• 716 Vario
• 717 Vario
• 718 Vario
• 916 Vario
• 920 Vario
• 924 Vario
• 926 Vario
• 930 Vario
• Fendt 300 Vario (COM III)
• Fendt 400 Vario / Farmer 400 (COM I, II, III)
• Fendt 700 Vario / Favorit 700 (COM I, II, III)
• Fendt 800 Vario (COM I, II, III)
• Fendt 900 Vario / Favorit 900 (COM I, II, III)

1. 1

   Verify the voltage supply for the CAN bus on the A013 fuse board, specifically checking fuses F040 and F041.

2. 2

   Inspect the CAN bus wiring harness and connectors between the A002 ECU and the A004 Control Console for physical damage, corrosion, or loose pins.

3. 3

   Test the passive bus system to ensure the bus ends are properly sealed off with terminating resistors.

4. 4

   Check for related CAN bus communication codes (such as B.1.41, B.1.42, or B.1.44) which might indicate a broader network issue pulling the bus down.

1. 1

   Power Down

   Turn off the tractor ignition and disconnect battery power before working on the electrical system.

2. 2

   Fuse Replacement

   Access the A013 fuse board. Test fuses F040 and F041. If blown, replace them and retest the system.

3. 3

   Harness Repair

   Remove the paneling on the right mudguard inside the cab to access the A004 Control Console and the A002 ECU. Disconnect the harnesses and clean the contacts. Repair any broken or chafed wires on the CAN bus lines connecting these two modules.

4. 4

   Component Replacement/Repair

   If the wiring and power supply are intact, the internal ECU belonging to the A004 Control Console or the A002 Enhanced Control ECU has failed. The A004 unit will need to be sent out for circuit board repair or replaced entirely.

5. 5

   Clear Fault Codes

   Once the repair is made, turn the ignition ON. Use the tractor's terminal to confirm, call up, and delete the stored fault codes from the tractor's memory.

6. 6

   System Test

   Perform a test run of the Variotronic TI (Teach-in) program to verify that communication has been restored and the error counter does not overflow again.