Fendt 09.1.E5 – A050 basic control unit: Y070 EHR cut-off valve, front - High overvoltage (> 45V)

High overvoltage (> 45V) at the Y070 EHR cut-off valve, causing the valve to move to neutral and lock, disabling the front power lift.

• 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)
• Fendt 922 Vario (COM III)
• Fendt 924 Vario (COM III)
• Fendt 927 Vario (COM III)
• Fendt 930 Vario (COM III)
• Fendt 933 Vario (COM III)
• Fendt 936 Vario (COM III)

1. 1

   Test the tractor's charging system (alternator and voltage regulator) with a multimeter to ensure it is not overcharging.

2. 2

   Inspect the wiring harness between the A050 ECU and the Y070 valve for chafed wires that may be shorting to a high-voltage source.

3. 3

   Disconnect the Y070 valve and check the connector pins for corrosion, water ingress, or bridging that could cause a short circuit.

4. 4

   Turn the ignition on and measure the voltage supply at the Y070 connector to verify if the overvoltage condition is actively present.

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the battery to prevent further electrical damage.

2. 2

   Resolve the Overvoltage Source

   If the alternator/voltage regulator is faulty and producing voltage spikes, replace the alternator assembly. If a short-to-power is found in the wiring harness, repair or splice the damaged section of the harness and secure it away from pinch points.

3. 3

   Inspect the Y070 Valve

   Test the resistance of the valve coil. If it is out of specification or internally shorted, the valve must be replaced.

4. 4

   Replace the Valve (if necessary)

   Relieve hydraulic pressure from the front power lift system. Locate the Y070 valve on the front hydraulic control block. Disconnect the electrical connector and hydraulic lines. Unbolt and remove the faulty valve, then install the replacement.

5. 5

   Reassemble and Calibrate

   Reconnect the battery, clear the stored 09.1.E5 fault code via the terminal, and test the front power lift to ensure the valve responds correctly without locking into neutral.