Fendt 18.1.69 – A057 - ECU, steering controller (Autoguide): Supply voltage is over 32 V at Y087 - Steering valve block, Auto-Guide

An overvoltage error indicating the electrical supply reaching the steering valve block has exceeded the safe operating threshold of 32 volts.

• 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 (COM III)
• Fendt 400 Vario (COM III)
• Fendt 700 Vario (COM III and SCR)
• Fendt 800 Vario (COM III and SCR)
• Fendt 900 Vario (COM III and SCR)
• Fendt 919 Vario
• Fendt 922 Vario
• Fendt 924 Vario
• Fendt 925 Vario
• Fendt 927 Vario
• Fendt 928 Vario
• Fendt 930 Vario
• Fendt 933 Vario
• Fendt 936 Vario

1. 1

   Check the tractor's alternator and voltage regulator for overcharging (voltage exceeding 32V)

2. 2

   Inspect the steering valve electrical supply line for a short to a higher voltage source (refer to wiring diagram sheets 38/39)

3. 3

   Disconnect the harness at separation points X1588/X1589 at the Y087 steering valve block and measure the supply voltage with a multimeter while the tractor is running

4. 4

   If supply voltage at the connector is normal, check for internal shorts in the Y087 steering valve block circuitry or position sensor

1. 1

   Access the Valve Block

   Safely park the tractor. To access the Y087 steering valve block, you must remove the right rear wheel and the right-side transmission panel.

2. 2

   Resolve Overvoltage (If Present)

   If your multimeter confirms voltage >32V at the harness, trace the wiring back to the A057 steering controller and the battery/alternator to repair the short or replace the faulty voltage regulator.

3. 3

   Replace the Valve Block (If Faulty)

   If the wiring and charging system are healthy, the Y087 valve block itself is defective. Disconnect the hydraulic lines (be prepared to catch residual hydraulic fluid) and the electrical connectors (X1588/X1589). Unbolt and remove the old valve block.

4. 4

   Install the New Valve Block

   Mount the new Y087 steering valve block, reconnect the hydraulic lines, and plug in the electrical connectors.

5. 5

   Calibrate the Steering Valve

   A newly installed Auto-Guide steering valve must be calibrated before it will function. Use the tractor terminal or FENDIAS diagnostic tool to run Calibration code "2403".

6. 6

   Reassembly

   Reinstall the right-side transmission panel and the right rear wheel. Clear the stored fault codes and test the Auto-Guide system in the field.