Fendt 15.1.64 – A039 (MFA, Multifunction Armrest) / A050 (ECU, Basic Control Unit): A039 - MFA, multifunction armrest. Button, raise suspension (VA suspension) - Faulty button, signal fault.

This code indicates an electrical signal fault originating from the button used to raise the front axle (VA) suspension, which is located on the multifunction armrest. The system has detected that the button is either shorted, open, or stuck, resulting in an invalid signal. The front axle suspension raise function becomes non-operable.

• 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 200 V/F/P Vario
• Fendt 300 Vario (COM III)
• Fendt 400 Vario (COM III)
• Fendt 700 Vario (COM III & SCR)
• Fendt 800 Vario (COM III & SCR)
• Fendt 900 Vario (COM III & SCR) (e.g., 916, 920, 922, 924, 927, 930, 933, 936)

1. 1

   Inspect the 'raise suspension' button on the MFA for physical damage, sticking, or debris lodged around the switch mechanism.

2. 2

   Use FENDIAS diagnostic software or the tractor's onboard terminal to monitor the live state of the A039 MFA buttons. Check if the 'raise suspension' button is permanently reading as 'ON' (stuck closed) or fails to register when pressed (open circuit).

3. 3

   Test the A039 component using a 160-pin adapter box to verify the electrical integrity of the armrest's internal wiring and switches.

4. 4

   Inspect the wiring harness and connectors between the A039 MFA and the A050 basic control unit for continuity, corrosion, or loose pins.

1. 1

   Prepare tractor

   Park the tractor on a level surface, lower any implements, turn off the engine, and disconnect the battery.

2. 2

   Access internal components

   Carefully remove the covers on the A039 multifunction armrest to access the internal switch matrix and wiring harness.

3. 3

   Locate switch

   Locate the specific microswitch/button assembly for the front axle (VA) suspension raise function.

4. 4

   Test switch

   Test the switch directly with a multimeter for continuity when pressed.

5. 5

   Repair or replace

   If the internal wiring is pinched or damaged, repair the harness. If the switch itself has failed, replace the switch. Note: On many modern Fendt armrests, individual buttons are integrated into a larger switch membrane or circuit board and cannot be serviced separately. In this case, the switch cluster or the entire MFA top module must be replaced.

6. 6

   Reassemble armrest

   Reconnect the wiring harnesses and reassemble the armrest housing.

7. 7

   Restore power

   Reconnect the battery and turn on the ignition.

8. 8

   Clear fault code

   Clear the stored 15.1.64 fault code using the tractor's terminal or FENDIAS software.

9. 9

   Test function

   Test the front axle suspension raise and lower functions to confirm the repair.

10. 10

    Perform EOL programming

    Important: If the entire A039 MFA was replaced, EOL (End of Line) programming and calibration of the armrest and joystick will be required via FENDIAS.