Fendt A.1.38 – A002 ECU: Spool valve fault, valve 3 (Y017) — Main piston cannot return to neutral position because of oil contamination

The main piston inside the auxiliary control valve (Valve 3 / VENDI, typically the red valve) is physically jamming or sticking due to dirt, debris, or foreign particles in the hydraulic oil. Because the spool cannot return to its neutral position, the system flags a critical safety hazard. Undefined and uncontrolled functions can occur.

• 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
• Fendt 300 Vario
• Fendt 400 Vario
• 409
• 410
• 411
• 412
• 413
• 414
• 415
• Fendt 700 Vario
• 711
• 712
• 714
• 716
• 718
• Fendt 800 Vario
• 815
• 817
• 818
• 820
• Fendt 900 Vario
• 916
• 920
• 924
• 926
• 930

1. 1

   Perform a manual actuation test on Valve 3 (Y017) to ensure the slider has no play and springs back to the middle (neutral) position by itself

2. 2

   Inspect the hydraulic fluid for visible contamination, metal shavings, or degraded oil quality

3. 3

   Check the control pressure to ensure it has not dropped below 22 bar, which can exacerbate spool travel issues

1. 1

   Relieve Pressure

   Safely relieve all hydraulic pressure from the system and lower any attached implements.

2. 2

   Access the Valve Block

   Access Y017 (Valve 3) on the underside of the central control block. You may need to unscrew and remove the right entrance step and pull the right auxiliary tank outwards.

3. 3

   Clean the Valve

   Remove the affected control block segment. Carefully clean the control block segments on the inside to remove dirt or foreign particles.

4. 4

   Address Fluid Contamination

   Drain the contaminated hydraulic oil, replace the hydraulic filters, and flush the system to ensure the prescribed oil cleanliness.

5. 5

   Reassembly / Replacement

   If the spool is scored or permanently damaged by the debris, replace the valve slice (SB23-EHS). Install the new or cleaned valve, replace the seals, and reassemble the block.

6. 6

   Calibration

   After replacing the valve, perform EOL (End of Line) programming/calibration to register the new valve position on the CAN bus.