Fendt 7.1.A2 – A002 ECU: Communication fault in COMFORT FRONT PTO

CAN-Bus communication loss or signal fault involving the A004 component (Front PTO 'Active' key / Control console). Logged against the A002 ECU due to loss of communication. Applies only to single e-box version tractors.

• 409 Vario
• 410 Vario
• 411 Vario
• 412 Vario
• 711 Vario
• 712 Vario
• 714 Vario
• 715 Vario
• 716 Vario
• 717 Vario
• 718 Vario
• 916 Vario
• 920 Vario
• 924 Vario
• 926 Vario
• 930 Vario
• Farmer 400 Vario
• Favorit 700 Vario
• Favorit 900 Vario
• Fendt 700 Vario (COM III)
• Fendt 800 Vario (COM III)
• Fendt 900 Vario (COM III)

1. 1

   Check for related codes (e.g., 0.0.13 or 7.1.09) on the terminal. If multiple components are failing to communicate, this points to a main CAN-Bus harness or A013 fuse board issue rather than an isolated switch failure.

2. 2

   Check the CAN-Bus power supply at the A013 printed circuit board (fuse board) and test fuses F040 and F041 (diagnosing a voltage supply loss cause).

3. 3

   Inspect the wiring harness and AMP Superseal plug connection between the A004 Front PTO switch and the A002 ECU for pinched wires, corrosion, or loose pins (diagnosing a wiring/connection cause).

4. 4

   Test the A004 Front PTO 'Active' key (yellow push button) for proper continuity when pressed (diagnosing a failed switch cause).

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the battery to prevent electrical shorts while working on the CAN-Bus system.

2. 2

   Replace Fuses

   If fuses F040 or F041 on the A013 board are blown, replace them with the correctly rated fuses.

3. 3

   Access the Control Console

   Carefully remove the trim or paneling around the A004 control console to access the rear of the Front PTO switch.

4. 4

   Disconnect and Clean

   Disconnect the 3-pin AMP Superseal connector from the switch. Clean the contacts with electrical contact cleaner. If the wiring is damaged, repair the harness.

5. 5

   Replace the Switch

   If the switch failed the continuity test, pop the faulty A004 switch out of the console and install the replacement yellow push-button switch.

6. 6

   Reassemble and Reconnect

   Reconnect the AMP Superseal plug, secure the console panels, and reconnect the tractor's battery.

7. 7

   Clear Fault Codes

   Turn the ignition on. Error codes are displayed on the dash panel (A007). Press and hold the confirmation key on the terminal to acknowledge and clear the fault message.

8. 8

   Test Operation

   Start the tractor and engage the Front PTO to ensure the communication fault does not return and the PTO operates normally.