Fendt 0A.1.F4 – Hydraulics Control Module / Electronic Lifting Gear Control (Enhanced Control ECU / A002): Electrical fault with component Y021 - Raise solenoid valve (standard front power lift)

The system has detected a short circuit to earth (ground), a short circuit to +UB (battery voltage), or a break in the wiring (open circuit) for the Y021 Raise solenoid valve. As a consequence, the front power lift is locked out of the raise function.

• 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)
• Fendt 800 Vario (COM III & S4 series)
• Fendt 900 Vario (COM III & S4 series)

1. 1

   Locate the Y021 solenoid valve on the front power lift hydraulic valve block and its electrical connector X332.

2. 2

   Disconnect connector X332 and inspect for moisture, corrosion, backed-out pins, or damaged terminals.

3. 3

   Using a multimeter, test the signal and ground wires from connector X332 back to the ECU for continuity (to rule out an open circuit) and for a short to ground or power.

4. 4

   Measure the internal resistance of the Y021 solenoid coil to determine if the coil has failed internally (open circuit or dead short).

1. 1

   Preparation

   Turn off the tractor, lower the front power lift to the ground (if possible) to relieve hydraulic pressure, and disconnect the battery.

2. 2

   Access the Valve

   Remove any necessary metal guards or panels to access the front power lift hydraulic control block.

3. 3

   Wiring Repair

   If the diagnostic checks revealed chafed wiring or a damaged X332 connector, splice in a new connector pigtail or repair the broken wire using weather-sealed heat shrink connectors.

4. 4

   Valve Replacement

   If the Y021 solenoid coil failed the resistance test: Clean the area around the valve to prevent dirt from entering the hydraulic system. Disconnect connector X332. Unscrew the retaining nut holding the solenoid coil to the valve stem, or unthread the entire cartridge valve depending on the specific block design. Install the new Y021 solenoid valve/coil and tighten to the manufacturer's specified torque.

5. 5

   Reassembly

   Reconnect connector X332 and reinstall any protective guards.

6. 6

   Calibration/Clearing

   Reconnect the battery, turn the ignition on, and use the tractor's onboard terminal (or FENDIAS diagnostic tool) to clear the stored 0A.1.F4 fault code. Test the front power lift to ensure the 'raise' function is restored.