Fendt 09.1.23 – MFA (Multifunction Armrest): MFA, multifunction armrest. Setpoint potentiometer, front power lift.

There is a signal fault or failure of the setpoint potentiometer used to control the front power lift (front EPC). Because the system cannot read the dial's position, setpoint values cannot be set. The front power lift will default to a locked state where only basic position control is possible.

• 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 400 Vario (COM III)
• Fendt 700 Vario (COM III, SCR, Gen6)
• Fendt 800 Vario (COM III, 820 greentec)
• Fendt 900 Vario (COM III, S4, SCR)

1. 1

   Inspect the front power lift rotary control dial on the MFA for physical damage, sticking, or liquid intrusion.

2. 2

   Check the internal wiring of the armrest, verifying the 8.5V reference voltage supply is present and the signal line is not shorted or open.

3. 3

   Attempt to recalibrate the front power lift sensors using Code 9001 (depth control) and Code 9002 (position sensor).

4. 4

   Look for accompanying CAN bus faults (e.g., 00.0.03 - MFA bus fault) that indicate the entire armrest has lost communication.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the battery to prevent electrical shorts while working inside the armrest.

2. 2

   Disassemble the MFA

   Carefully remove the top cover/bezel of the multifunction armrest to expose the internal circuit boards and rotary dials.

3. 3

   Remove the Faulty Potentiometer

   Locate the specific potentiometer for the front power lift setpoint. Disconnect its wiring harness/ribbon cable from the main MFA board. Remove the retaining nut or mounting screws securing it to the armrest housing.

4. 4

   Install the New Component

   Fit the replacement potentiometer into the housing, secure the retaining hardware, and plug the connector back into the board.

5. 5

   Reassembly

   Carefully reassemble the armrest, ensuring no wires are pinched. Reconnect the tractor battery.

6. 6

   Clear Fault Codes

   Turn the ignition on. Navigate to the fault code menu on the Vario terminal. Press the confirm button repeatedly to clear the stored 09.1.23 code (Fendt requires each stored code to be cleared individually).

7. 7

   Perform Calibration

   You must calibrate the new potentiometer for it to work. Access the calibration menu and run Code 9001 (Front EPC setpoint potentiometer calibration).

8. 8

   Test Operation

   Verify that the front power lift responds correctly to the dial without throwing the code again.