Fendt A.1.65 – A057 - ECU, Steering Controller (Auto-Guide): Y087 - Steering valve block, Auto-Guide (or VarioGuide)

Unidentified fault in the steering valve. The system has detected a malfunction within the automated steering valve block (Y087) that cannot be specifically categorized as a simple voltage drop or open circuit.

• 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
• Fendt 200 Vario V/F/P series
• Fendt 300 Vario (COM III)
• Fendt 400 Vario (COM III)
• Fendt 500 Vario (S4)
• Fendt 700 Vario (COM III, S4, Gen7)
• Fendt 800 Vario (COM III, S4)
• Fendt 900 Vario (COM III, S4, Gen6)

1. 1

   Check the wiring harness and connectors leading to the Y087 steering valve block (specifically checking separation points X1588 and X1589 on the right side of the transmission) for broken wires or short circuits.

2. 2

   Verify the supply voltage to the steering valve (drops below 10V or spikes above 32V will disable the valve).

3. 3

   Ensure there is adequate hydraulic oil in the steering valve and that the system pressure upstream of the high-pressure filter is within spec.

4. 4

   Verify that the seat contact switch is functioning properly, as the steering valve will not actuate if the seat is not loaded.

1. 1

   Access the Valve

   Locate the Y087 steering valve block on the right side of the transmission. You may need to remove the right rear wheel and access panel depending on the specific Vario model.

2. 2

   Component Replacement

   If wiring and voltage are confirmed good but the unidentified fault persists, the internal components of the steering valve have failed. Replace the steering valve block (Y087) or the steering head.

3. 3

   Reconnection & Leak Test

   Install the new steering valve bracket and valve. Reconnect the hydraulic hoses and electrical connectors. Start the tractor and check for hydraulic oil leaks.

4. 4

   Mandatory Calibration

   Enter Calibration Code 2403 (VarioGuide steering valve calibration) into the tractor's terminal to learn the new valve slider free travel. Ensure no people or objects are in the steering area, as front wheels will deflect automatically. The operator must remain in the seat during the entire process to keep the seat contact switch closed until an 'OK' is displayed.