Fendt 0F.1.23 – A050 - ECU, basic control unit: Communication problem: no information from transmission (engine speed, theoretical speed, reverse operation).

Loss of data on the transmission CAN bus. The control unit is no longer receiving critical speed and directional data from the transmission sensors (such as the Hall sensors on the collecting shaft and bevel pinion).

• 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 / SCR)
• 400 Vario (COM III)
• 500 Vario (SCR)
• 700 Vario (COM III / SCR)
• 800 Vario (COM III)
• 900 Vario (COM III / SCR / Gen6)

1. 1

   Check for Related Codes: Look for accompanying codes like 0F.1.24 (no info from enhanced controls/brake) or 0F.1.25 (no info from multifunction armrest). Multiple '0F.1.xx' codes usually point to a broader CAN bus failure or a failing A050 ECU.

2. 2

   Inspect Transmission Sensors: Check the transmission speed sensors (specifically the B014 Hall sensor on the collecting shaft and the B015 Hall sensor on the bevel pinion) which measure rotational speed and direction.

3. 3

   Wiring and Harness Check: Inspect the transmission CAN bus wiring harness between the transmission sensors and the A050 ECU. Look for chafed wires, corrosion, or loose pins at the ECU connectors.

4. 4

   Test the A050 ECU: Use a 160-pin adapter box to test the inputs and outputs of the A050 ECU to verify if the internal CAN transceiver has failed.

1. 1

   Verify the Fault

   Call up the fault code on the tractor's terminal to confirm it is active.

2. 2

   Repair Wiring/Sensors

   If diagnostic checks reveal a damaged transmission CAN bus wire or a faulty Hall sensor (B014/B015), repair the harness or replace the sensor.

3. 3

   Address the A050 ECU

   If the wiring and sensors are intact, the A050 basic control unit has likely suffered an internal communication failure. The unit must be removed and either sent to a specialized agricultural electronics repair service or replaced with a new/remanufactured unit.

4. 4

   EOL Programming

   If the A050 ECU is replaced or wiped, it must undergo EOL (End of Line) programming using FENDIAS diagnostic software (version 7.60 or higher) to match the tractor's specific configuration.

5. 5

   Clear Fault Codes

   Fault codes stored in the A050 ECU cannot be permanently deleted via the dashboard terminal; they must be cleared using the FENDIAS diagnostic software.