Fendt 18.1.3A – Autoguide / VarioGuide steering controller: Y087 - Steering valve block, Autoguide (or VarioGuide) - No response from valve.

The tractor's control system has lost communication with or is not receiving a valid feedback signal from the automated steering proportional valve (Y087). This valve is responsible for executing GPS-guided steering commands.

• 922 Vario COM III
• 924 Vario COM III
• 927 Vario COM III
• 930 Vario COM III
• 933 Vario COM III
• 936 Vario COM III
• Fendt 300 Vario series
• Fendt 400 Vario series
• Fendt 500 Vario series
• Fendt 700 Vario series (COM III and SCR/S4)
• Fendt 800 Vario series (COM III and SCR/S4)
• Fendt 900 Vario series (COM III and SCR/S4)

1. 1

   Check the electrical supply line and CAN communication wiring to the Y087 steering valve block for breaks, chafing, or short circuits

2. 2

   Verify the supply voltage at the steering valve connector (must be between 10V and 32V)

3. 3

   Check the position sensor wiring for shorts or open circuits

4. 4

   Check if the steering valve has lost its calibration data in the EEPROM

1. 1

   Access the Valve Block

   The Y087 steering valve block is typically located on the right side of the transmission. To gain full access, safely support the tractor, remove the right rear wheel, and remove the inner side panel.

2. 2

   Inspect Connectors

   Disconnect the wiring harness at the Y087 valve (look for separation points X1588 / X1589). Clean the contacts with electrical contact cleaner and inspect for pushed-out pins or moisture intrusion.

3. 3

   Test the Harness

   Using a multimeter, perform a continuity test on the wiring harness from the Y087 connector back to the steering controller/ECU to rule out a broken wire.

4. 4

   Replace the Valve

   If the wiring harness, connectors, and voltage supply are all in good condition, the internal electronics or the position sensor of the Y087 steering valve block have failed. The valve block assembly must be replaced.

5. 5

   System Calibration

   After repairing the wiring or replacing the valve block, the steering system must be recalibrated. Enter Calibration Code '2403' into the tractor's terminal to teach-in the new valve and establish its reference positions.