Fendt 08.1.F0 – A050 ECU (Basic Control Unit): Y077 - EHR cut-off valve, rear. Valve does not report to CAN bus.

The rear Electronic Hitch Control (EHR) cut-off valve has lost communication with the tractor's Controller Area Network (CAN bus / V bus). The valve moves to neutral and locks. No actuation of the rear power lift is possible.

• 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 700 Vario series
• Fendt 800 Vario series
• Fendt 900 Vario series (e.g., 922, 924, 927, 930, 933, 936)

1. 1

   Visually inspect the Y077 valve electrical connector on the rear hydraulic valve block for moisture, corrosion, or backed-out pins.

2. 2

   Test the CAN bus wiring (V bus) between the Y077 valve and the A050 ECU for open circuits, shorts to ground, or shorts to power.

3. 3

   Perform a passive bus check with the battery disconnected by measuring resistance across the CAN bus pins at the valve connector to verify terminating resistors (should read ~60 ohms).

4. 4

   Verify that the valve is receiving proper operating voltage and has a clean ground connection.

5. 5

   Check the hydraulic fluid for heavy contamination, which can cause the valve actuator to mechanically jam and interrupt initialization.

1. 1

   Preparation

   Park the tractor on a level surface. Lower the rear hitch completely to the ground to remove mechanical load.

2. 2

   Depressurize

   Turn off the engine. Relieve all hydraulic pressure in the system (actuate valves/steering as per standard Fendt depressurization procedures).

3. 3

   Clean the Area

   Thoroughly clean the rear valve block around the Y077 valve to prevent dirt from entering the hydraulic system during removal.

4. 4

   Removal

   Disconnect the electrical harness from the Y077 valve. Unbolt the valve from the rear end plate/manifold and carefully remove it.

5. 5

   Installation

   Lubricate the O-rings on the new EHR cut-off valve with clean hydraulic oil. Seat the valve into the block and tighten the mounting bolts to the OEM torque specification. Reconnect the electrical harness.

6. 6

   Testing & Calibration

   Start the tractor and allow the hydraulic oil to reach operating temperature (40-50°C). Check the valve block for leaks. Clear the 08.1.F0 fault code from the terminal. Unlock the EHR system and test the rear power lift through its full range of motion.