Fendt 06.1.01 – MFA (Multifunction Armrest) module (A039) / Control Panel / Comfort Actuation module (A036): A039 - MFA, multifunction armrest Button in cab, rear PTO

Signal fault originating from the rear PTO ON/OFF button located in the cab. The system detects that the button is faulty, there is a signal interruption, or there is a bus communication fault. As a direct safety consequence, the rear PTO disengages and cannot be operated normally.

• 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 and SCR)
• Fendt 800 Vario (COM III and SCR)
• Fendt 900 Vario (COM III and SCR)

1. 1

   Inspect the yellow rear PTO ON/OFF button in the cab for physical damage, sticking, or mechanical failure.

2. 2

   Check the wiring harness and plug connections (AMP Superseal connectors) at the back of the switch for corrosion, moisture ingress, or loose pins.

3. 3

   Verify that there are no broader CAN bus communication errors between the MFA (A039) and the basic control unit (A050).

4. 4

   Use FENDIAS diagnostic software to monitor the live signal state of the button to confirm if the switch is stuck open or closed.

1. 1

   Disconnect Power

   Disconnect the tractor's battery to prevent electrical shorts during the repair.

2. 2

   Access the Switch

   Remove the necessary trim panels on the multifunction armrest (MFA) or side control console to access the rear of the PTO switch.

3. 3

   Disconnect Wiring

   Unplug the existing wiring harness connection from the faulty PTO switch.

4. 4

   Remove the Switch

   Pop the faulty switch out of its mounting location in the armrest/console.

5. 5

   Install the New Part

   Push the new replacement switch into the factory mounting hole until it clicks into place.

6. 6

   Reconnect

   Reconnect the wiring harness to the new switch, ensuring the weather-sealed connection is tight. Reconnect the tractor's battery.

7. 7

   Clear Codes

   Turn the ignition on and clear the stored 06.1.01 fault code using the tractor's terminal display or FENDIAS software.

8. 8

   Test

   Start the tractor and test the rear PTO engagement to ensure smooth, positive control and that the code does not return.