Fendt 8.3.28 – A004 - Control Console ECU: Fault in rear EPC quick lift switch

The system has detected a signal line fault, a faulty switch, or a contact error between the switch and the control module. Because the main cab switch is malfunctioning, the system locks out the internal controls for safety. The 'Raise' and 'Lower' functions for the rear electrohydraulic power control (EPC) linkage are disabled in the cab and are only possible using the external pushbuttons located on the rear fenders.

• 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 300 Vario series
• Farmer 400 Vario series
• Favorit 500 series
• 815 Vario
• 817 Vario
• 818 Vario
• 820 Vario

1. 1

   Check the safety lock by pressing the quick lift switch beyond the 'Stop' position until the indicator lamps light up to release the lock

2. 2

   Verify that the lifting height limitation rotary control is not accidentally set to the minimum lift position

3. 3

   Test the external rear fender buttons; if the linkage raises and lowers normally, the issue is isolated to the A004 console or the cab switch

4. 4

   Inspect fuses F040 and F041 on fuse board A013, which supply CAN-Bus voltage to the A004 Control Console

5. 5

   Inspect the plug connections at the A004 console for loose pins, moisture ingress, or corrosion

1. 1

   Preparation

   Relieve the rear lifting gear of any load by lowering the implement to the ground using the external fender buttons. Switch off the engine and disconnect the battery.

2. 2

   Console Access

   Carefully remove the trim panels on the right-hand armrest/side console to access the underside of the A004 Control Console ECU.

3. 3

   Switch Removal

   Locate the rear EPC quick lift switch. Disconnect its electrical plug connection. Depending on the exact tractor model, the switch will either unclip from the mounting board or require unscrewing.

4. 4

   Switch Installation

   Clean the connections thoroughly and apply dielectric grease to prevent future corrosion. Install the new switch into the console and reconnect the wiring harness.

5. 5

   Board-Level Alternative

   If your specific A004 control console has the switch soldered directly onto a printed circuit button board, the entire board may need to be replaced, or the console can be sent to an agricultural electronics specialist (such as Ilgenfritz Mechatronics) for board-level repair.

6. 6

   Reassembly and Testing

   Reassemble the console trim, reconnect the battery, turn on the ignition, and clear the fault codes via the Vario terminal. Test the lift and lower functions using the new cab switch.