Fendt A.1.2F – A002 ECU (Enhanced Control ECU): Y016 - Spool valve fault, valve 2 — Setpoint message is missing or not plausible.

The tractor's control system is not receiving a valid target position (setpoint) command for the #2 auxiliary hydraulic spool valve (color-coded blue). The system flags this as either a missing/implausible setpoint message, a missing configuration message, or a direct potentiometer/PWM (Pulse Width Modulation) fault. As a safety precaution, the system disables the valve, and it automatically defaults to the neutral position.

• 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 (409, 410, 411, 412)
• Favorit 700 Vario (711, 712, 714, 716)
• Favorit 900 Vario (916, 920, 924, 926, 930)
• COM III Vario Series (300, 400, 700, 800, and 900 series)

1. 1

   Open the 'SPOOL VALVES 1 - 4 setpoint / actual value display' on the Varioterminal, actuate the control for Valve 2 (blue), and observe if the setpoint changes to verify if the issue is on the input side.

2. 2

   Test the potentiometer or PWM signal coming from the joystick/fingertip control lever for Valve 2, looking for dead spots or erratic voltage/PWM readings.

3. 3

   Inspect connector X327 (specifically pins 23, 24, and 26) at the Y016 valve for corrosion, pushed-out pins, or moisture ingress.

4. 4

   Verify the integrity of the CAN II bus communication (specifically pins 4 and 5) between the A002 ECU and the valve block.

5. 5

   Verify if the tractor's ECU has lost its EOL (End of Line) programming for this valve, as the code can trigger from a missing configuration message.

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the battery before servicing CAN bus or ECU wiring.

2. 2

   Repair Wiring

   If diagnostic checks reveal damaged wiring between the A002 ECU, the joystick, or the X327 connector at the Y016 valve, repair the harness or replace the damaged connector pins.

3. 3

   Replace Input Control

   If the terminal display showed no setpoint change and the joystick potentiometer failed the electrical test, replace the faulty joystick or fingertip control module.

4. 4

   Replace the Spool Valve

   If the wiring, CAN bus, and input signals are all verified as good, the internal electronics (VENDI) of the Y016 spool valve have failed. Remove the hydraulic pressure from the system, unbolt the #2 (blue) auxiliary spool valve from the rear valve stack, and install a replacement unit.

5. 5

   Reprogramming

   If a new valve is installed, or if the ECU lost its configuration, connect the FENDIAS diagnostic tool. Perform EOL (End of Line) programming to configure the new auxiliary control valve for position 2 (blue) on the CAN bus.