Fendt 8.3.43 – A004 Control Console: Automatic function (switching from control console to joystick) — Fault in switch / A004 contact

This fault code indicates that the automatic rear lifting gear key (switch) on the control console is defective, or there is a signal/contact fault. Because of this fault, the system cannot switch the automatic lifting gear function from the control console to the joystick, rendering the automatic rear lifting gear key non-operational.

• 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
• 411 Vario COM III
• 412 Vario COM III
• 413 Vario COM III
• 414 Vario COM III
• 415 Vario COM III
• 712 Vario COM III
• 714 Vario COM III
• 716 Vario COM III
• 718 Vario COM III
• 818 Vario COM III
• 820 Vario COM III
• Farmer 400 series (409, 410, 411, 412)
• Favorit 700 / 700 Vario series (711, 712, 714, 715, 716, 717)
• Favorit 900 / 900 Vario series (916, 920, 924, 926, 930)
• 800 Vario series (815, 817, 818, 820)
• 300 Vario (COM III)

1. 1

   Verify the code using the tractor's terminal or the FENDIAS diagnostic tool to confirm code 8.3.43 is active.

2. 2

   Physically inspect the automatic rear lifting gear key on the A004 control console for sticking, debris, or physical damage.

3. 3

   Consult the 'Electrohydraulic power lift control' circuit diagram in the Fendt workshop manual.

4. 4

   Check for accompanying CAN (K-Bus) faults (such as A004 / A005 communication errors) which might indicate a wiring harness issue rather than a failed switch.

5. 5

   Test the electrical contacts of the switch for continuity to determine if the signal is reaching the A004 control console.

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the battery to prevent electrical shorts during console disassembly.

2. 2

   Access the A004 Console

   Remove the necessary trim panels on the right-hand mudguard/armrest to access the A004 Control Console.

3. 3

   Inspect Wiring

   Check the wiring harness connectors plugging into the A004 console for corrosion, backed-out pins, or damage. Clean with contact cleaner if necessary.

4. 4

   Replace the Switch/Keypad

   If the diagnostic tests prove the automatic rear lifting gear switch is internally shorted or open, replace the defective switch. Note: On many Vario models, the switches are integrated into a larger keypad membrane or the console itself, which may require replacing the keypad section or sending the A004 unit out for board-level repair.

5. 5

   Reassemble and Calibrate

   Reconnect the A004 console and restore battery power.

6. 6

   Clear Faults

   Clear the stored 8.3.43 fault code using the terminal or FENDIAS tool.

7. 7

   Functional Test

   Test the automatic rear lifting gear function to ensure it successfully switches control from the console to the joystick without logging the error.