Fendt 08.1.A4 – A050 - ECU, basic control unit: Y077 - EHR cut-off valve, rear - Flash_Test failure

Internal memory, software, or logic failure during the self-test (Flash memory test) of the valve's electronics or the ECU's control over it. As a safety measure, the valve moves to neutral and locks, disabling the rear power lift functionality.

• 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)
• Fendt 900 Vario (COM III)

1. 1

   Check for related memory fault codes (e.g., 08.1.A0, 08.1.A1, 08.1.A2, 08.1.A3) that indicate EEPROM or RAM errors on the Y077 valve

2. 2

   Inspect the wiring harness and connectors between the A050 Basic Control Unit and the Y077 rear EHR cut-off valve for corrosion, moisture ingress, or damaged pins

3. 3

   Verify that the valve is receiving the correct operating voltage from the ECU

4. 4

   Connect the FENDIAS diagnostic tool to attempt clearing the code and performing a software reset or EOL programming

1. 1

   Preparation

   Park the tractor on a level surface, lower any attached implements to the ground, turn off the engine, and disconnect the battery.

2. 2

   Relieve Pressure

   Relieve all hydraulic pressure from the rear hydraulic system to prevent injury.

3. 3

   Locate the Valve

   Locate the Y077 EHR cut-off valve on the rear hydraulic control block assembly.

4. 4

   Disconnect

   Carefully unplug the electrical harness from the valve.

5. 5

   Removal

   Unbolt and remove the faulty Y077 EHR cut-off valve from the hydraulic block. Be prepared to catch residual hydraulic fluid.

6. 6

   Installation

   Install the replacement valve using new O-rings/seals. Torque the mounting bolts to Fendt OEM specifications.

7. 7

   Reconnection

   Reconnect the electrical harness and the tractor's battery.

8. 8

   Calibration

   Connect the FENDIAS diagnostic tool. You must perform EOL (End of Line) programming/calibration for the new valve so the A050 ECU recognizes it and assigns the correct valve code.

9. 9

   Testing

   Start the tractor, check for hydraulic leaks, and test the rear power lift / EHR system for proper operation. Verify that code 08.1.A4 has been cleared.