Fendt A.1.36 – Tractor / General System ECU: Spool valve fault, valve 3 — Magnet output stage fault within spool valve

The internal electronics of the spool valve (specifically the output stage that controls the magnet/solenoid for pilot control) have failed or detected an internal electrical fault, causing the valve to automatically move into the neutral position and remain locked out to prevent uncontrolled hydraulic functions.

• 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
• 300 Vario COM III series
• 400 Vario COM III series
• 700 Vario COM III series
• 800 Vario COM III series
• 900 Vario COM III series

1. 1

   Identify Valve 3 (Component Y017), typically located in position 3 and color-coded red.

2. 2

   Check for related supply voltage codes (e.g., A.1.32 for low voltage < 8V or A.1.35 for overvoltage > 45V) which could simulate an internal valve fault.

3. 3

   Inspect the wiring harness and the connector at Valve 3 (Y017) for corrosion, moisture ingress, or damaged pins.

4. 4

   Verify that the valve is communicating on the CAN bus (check for code A.1.30 which indicates the valve cannot be recognized).

1. 1

   Access the Valve Block

   Safely park the machine, relieve all hydraulic pressure, and access the central control block (usually requires removing the right entrance step and pulling out the right auxiliary tank depending on the model).

2. 2

   Isolate the Fault

   Swap the electrical connector from Valve 3 (Y017) with an adjacent valve (e.g., Valve 4 / Y018). If the fault code changes to the new valve position (e.g., A.1.46), the issue is definitively inside the valve's electronic head.

3. 3

   Replace the Valve

   Because the magnet output stage is integrated into the valve's electronics, the electronic actuator head (or the entire spool valve slice, depending on the specific block design) must be replaced.

4. 4

   EOL Programming

   After installing the new valve, connect the FendtEST diagnostic tool. The new auxiliary control valve must be programmed and calibrated for position 3 in the EOL (End of Line) program so the tractor's ECU recognizes it.