Fendt 1.2.23 – Transmission/Enhanced Control Bus: CAN communication fault (message failure or timeout) between the Enhanced Control Module (EST) and the Electronic Diesel Control (EDC) module

When communication drops for more than 5 seconds, the tractor loses its enhanced throttle features. The system defaults to the EDC pedal position sensor, meaning the operator will only have access to the foot throttle. Hand throttle, memory keys, and terminal settings will be disabled.

• 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 Farmer 400 Vario
• Fendt Favorit 700 Vario
• Fendt Favorit 900 Vario
• Fendt 300, 400, 700, 800, and 900 Vario Series (including COM III generations)

1. 1

   Check CAN-bus power supply by inspecting Fuse Board A013 (specifically fuses F040 and F041) to ensure modules are receiving power.

2. 2

   Inspect physical connections at the EST Control Module A002 (Connector X031) and the EDC Control Module A021 (Connector X048) for backed-out pins, corrosion, or moisture.

3. 3

   Measure CAN-Bus resistance with the ignition OFF and an adapter box connected between Pin B11 and Pin B12 on the EDC Control Module A021 (Connector X048). Verify against chassis wiring diagram (requested value of 160 Ohms for a specific test block, though standard CAN health is typically 60 Ohms).

4. 4

   Test for disrupted wires, open circuits, or short circuits along the Transmission-BUS routing between the cab and the engine.

1. 1

   Power Down

   Turn the ignition OFF and disconnect the battery before servicing the CAN-bus wiring or modules.

2. 2

   Repair Wiring/Connectors

   If the diagnostic checks reveal a broken wire or corroded pin at Connector X031 (EST) or X048 (EDC), splice in new CAN-bus wiring or replace the damaged connector pins.

3. 3

   Replace Fuses/Board

   If the fuses on board A013 are blown, replace them. If the fuse board itself has an internal short or failure, replace Fuse Board A013.

4. 4

   Module Replacement (If Necessary)

   If the wiring harness, connectors, and power supply are all perfectly intact but the CAN timeout persists, replace the EDC Control Module (A021) or EST Control Module (A002). (Note: Module replacement will require EOL (End-of-Line) programming using FENDIAS).

5. 5

   Clear Codes

   Reconnect the battery, turn the ignition ON, and use the FENDIAS diagnostic software to record failure parameters and delete the fault code memory.

6. 6

   Verify Operation

   Test the tractor to ensure the hand throttle and memory keys have regained functionality.