Fendt 04.1.E0 – A050 - ECU, basic control unit: Turbo-clutch characteristic has been read incorrectly or the wrong characteristic is stored

Fault code 04.1.E0 indicates that the turbo-clutch characteristic has been read incorrectly or the wrong characteristic is stored in the system's memory. The Y004 component is the transmission neutral / turbo-clutch solenoid valve. When this fault is triggered, the tractor will typically allow continuation of work, but only in a restricted 'emergency mode'.

• 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 (e.g., 309, 310, 311, 312)
• Fendt 400 Vario series (Farmer 400)
• Fendt 700 Vario series (Favorit 700)
• Fendt 800 Vario series
• Fendt 900 Vario series (Favorit 900, 916, 920, 922, 924, 926, 927, 930, 933, 936, 939 COM III and S4 generations)

1. 1

   Check the wiring harness and separation points to the Y004 solenoid valve (located on the right side of the transmission) for breaks, short circuits, or PWM supply failures.

2. 2

   Ensure the transmission oil is at the correct level and temperature. Check if the S017 switch is indicating a clogged transmission oil filter, as hydraulic pressure issues can mimic valve failures.

3. 3

   Check that the tractor's sensors are reading correctly to allow for a calibration. The tractor must be completely stationary (<0.1 km/h), the handbrake must be applied, and the engine speed must be capable of holding a steady 1100 ± 40 rpm.

1. 1

   Secure the Tractor

   Pull the handbrake tight. Warning: The tractor may start moving or lurch during this calibration process.

2. 2

   Start the Engine

   Turn on the tractor and let it idle.

3. 3

   Set Engine Speed

   Adjust the engine speed to exactly 1100 +/- 40 rpm. (Note: The engine speed may drop slightly during the calibration sequence).

4. 4

   Initiate Calibration

   Access the tractor's terminal/dashboard diagnostic menu and execute Calibration code 4009.

5. 5

   Monitor for Calibration Faults

   If the calibration fails, the dashboard will output a specific 'F' code. For example: F20: Fault in Y004 turbo clutch solenoid valve. F21 / F23: Plausibility error / power consumption of Y004 is too high (e.g., a short circuit in the valve).

6. 6

   Replace Valve (If Calibration Fails)

   If calibration fails with F20/F21/F23, the Y004 solenoid valve is mechanically jammed or electrically shorted and must be replaced.

7. 7

   EOL Programming

   If the calibration completes but the A050 ECU drops the memory again (EEPROM error), the basic control unit will require EOL (End of Line) programming by a dealer, or the A050 module itself must be repaired/replaced.