Fendt 08.1.F2 – EHR (Electronic Hitch Control) / A050 - ECU: Undervoltage (U < 8V) at Y077 - EHR cut-off valve, rear

Voltage has dropped below the minimum 8-volt threshold required for operation, forcing the valve to move to neutral and lock as a safety measure, disabling the rear power lift actuation.

• 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) / Farmer 400
• Fendt 700 Vario (COM III & SCR) / Favorit 700
• Fendt 800 Vario (COM III)
• Fendt 900 Vario (COM III & SCR) / Favorit 900

1. 1

   Perform a system reset by turning the ignition off and back on to see if the voltage dip was temporary

2. 2

   Read active codes using the dash panel, Varioterminal, or a diagnostic tool to confirm if the fault is active or historical

3. 3

   Perform a voltage drop test by probing the electrical connector at the Y077 valve to verify if voltage drops below 8V under load

4. 4

   Inspect the wiring harness and bus linking the A050 ECU to the Y077 valve for corroded pins, chafed wires, or loose grounds

1. 1

   Power Cycle

   Turn the tractor off and on to attempt a basic module reset.

2. 2

   Locate the Valve

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

3. 3

   Inspect Connections

   Disconnect the solenoid plug. Clean the contacts with electrical contact cleaner and ensure the pins are tight.

4. 4

   Repair Wiring

   If your multimeter shows less than 8V arriving at the connector when the circuit is energized, trace the harness back to the ECU and repair the damaged wire or bad ground causing the voltage drop.

5. 5

   Replace Solenoid/Valve

   If the wiring provides proper voltage but the solenoid coil is internally shorted (pulling the voltage down) or fails to actuate, replace the Y077 solenoid valve.

6. 6

   Clear Faults

   Once repaired, clear the fault codes. On the Varioterminal, this can often be done by accessing the LBS Diagnostics Menu (pressing F2) or using a dedicated diagnostic scanner.