Fendt 08.1.44 – A039 - MFA (Multifunction Armrest): A039 - MFA, multifunction armrest stop button, rear power lift

This fault code indicates a signal fault or electrical error originating from the rear power lift stop button located on the tractor's multifunction armrest. The system has detected that the button is faulty or sending an invalid signal.

• 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 & SCR)
• Fendt 800 Vario (COM III & SCR)
• Fendt 900 Vario (COM III & SCR)
• Fendt 922
• Fendt 924
• Fendt 927
• Fendt 930
• Fendt 933
• Fendt 936

1. 1

   Check the rear power lift stop button on the armrest for physical damage, debris, or sticking

2. 2

   Turn the ignition OFF, wait briefly, and turn it back ON to see if a cold start reset clears the fault

3. 3

   Test the external rear power lift buttons on the rear fenders to confirm the issue is isolated strictly to the armrest module

4. 4

   Monitor the live signal from the MFA module using a 160-pin adapter box or FENDIAS diagnostic software to verify button registration

1. 1

   Power Down

   Turn off the tractor ignition and disconnect the battery to prevent electrical shorts while working on the armrest bus.

2. 2

   Access the MFA

   Carefully remove the top cover/bezel of the multifunction armrest to expose the internal keypad and wiring.

3. 3

   Inspect Wiring

   Check the ribbon cables and wiring harness connecting the rear power lift button to the main A039 circuit board. Look for pinched wires, chafing, or moisture corrosion.

4. 4

   Replace the Component

   If the wiring is intact but the button fails continuity testing, replace the faulty switch. (Note: Depending on the exact armrest revision, this may require replacing the specific keypad cluster rather than an individual microswitch).

5. 5

   Reassembly

   Reassemble the armrest console and reconnect the battery.

6. 6

   Initialization

   Perform a cold start to allow the A039 module to initialize without the signal fault.

7. 7

   Clear Codes

   Clear the stored 08.1.44 fault code using the tractor's dashboard diagnostic menu or FENDIAS software, then test the rear power lift stop button for proper operation.