Fendt 0.0.14 – Transmission Control Unit (A009 Actuator Unit): Transmission control unit - Bus fault

Loss of CAN bus communication with the transmission control unit. When this code is active, the tractor will typically experience a complete loss of transmission functions and display readouts. The tractor may default to an emergency mode where the transmission can only be operated manually via the mechanical emergency control system.

• 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
• Farmer 400 series
• Favorit 700 and 900 series
• 300, 400, 700, 800, and 900 Vario series (including COM I, COM II, COM III, and S4 generations)

1. 1

   Check the voltage supply for the CAN bus on the A013 printed circuit board / fuse board

2. 2

   Inspect fuses F040 and F041 on the A013 fuse board, which protect the CAN bus power supply for the transmission control module

3. 3

   Check the CAN bus wiring harness for continuity, shorts to ground, or breaks between the A013 fuse board and the A009 Transmission Control Unit

1. 1

   Access the A013 Fuse Board

   Locate the A013 printed circuit board/fuse board (location varies slightly by cab design, usually in the main electrical console).

2. 2

   Test Fuses F040 and F041

   Use a multimeter to test for continuity across fuses F040 and F041. Replace them if blown.

3. 3

   Trace for Shorts

   If the fuses immediately blow again upon key-on, trace the wiring harness from the A013 board to the A009 actuator unit to locate the short circuit.

4. 4

   Verify Voltage

   If the fuses are good, verify that the A013 board is actually outputting the correct voltage to the CAN bus pins. A damaged A013 circuit board can fail internally and drop the voltage.

5. 5

   Inspect the A009 Connector

   Disconnect the harness at the A009 Transmission Control Unit. Inspect the pins for corrosion, moisture ingress, or backed-out terminals. Clean and reseat the connector.

6. 6

   Component Replacement

   If power, ground, and CAN continuity are all verified at the A009 connector, the A009 Actuator Unit itself has likely failed and requires replacement. Alternatively, if the A013 board is not outputting power, the A013 board must be replaced.