Fendt 04.1.A2 – A009 Actuator unit / A050 Basic control unit: CAN bus actuation fault

Faulty CAN bus connection to the control unit between the A009 Actuator unit and the A050 Basic control unit. The tractor can usually continue to operate in emergency/auxiliary mode.

• 922 Vario COM III
• 924 Vario COM III
• 927 Vario COM III
• 930 Vario COM III
• 933 Vario COM III
• 936 Vario COM III
• Fendt 300 Vario COM III
• Fendt 400 Vario COM III
• Fendt 700 Vario COM III (e.g., 711, 712, 714, 716)
• Fendt 800 Vario COM III (e.g., 815, 817, 818)
• Fendt 900 Vario COM III (e.g., 916, 920, 924, 926, 930, 936)

1. 1

   Verify if the tractor can still be driven in emergency/auxiliary mode

2. 2

   Check the CAN bus communication lines between the A009 actuator unit and the A050 basic control unit

3. 3

   Check the voltage level of the CAN bus (positive and negative cables) at the CAN bus sockets to ensure proper data transmission

4. 4

   Reference Chapter 9000 Reg. E in the workshop manual for exact pinout and testing procedures

1. 1

   Inspect Wiring

   Thoroughly inspect the CAN bus wiring harness connecting the A009 Actuator unit to the A050 Basic control unit for breaks, shorts, or severe corrosion. Repair any damaged wiring.

2. 2

   Check Connections

   Ensure the connectors at both the A009 and A050 modules are securely seated and free of moisture or bent pins.

3. 3

   Module Replacement

   If the wiring and CAN bus voltage levels test perfectly, one of the control units (A009 or A050) may have an internal failure and require replacement or professional repair.

4. 4

   Reprogramming

   If the A050 Basic control unit is replaced, EOL (End of Line) programming will be necessary to configure the new module to the tractor. Fault codes must be cleared from the A050 using the appropriate FENDIAS diagnostic software.