Fendt 4.1.B1 – Transmission Control Unit (TCU): Y001, Y002 - Speed range control — Illogical speed range operation

This code indicates a fatal error in the transmission's range control system. It is triggered when there is an illogical speed range operation, such as the values for shifting from range II to I falling outside of acceptable tolerances, or a direct actuation fault/supply failure to the travel range solenoid valves. The tractor will default to emergency mode.

• 409 Vario
• 410 Vario
• 411 Vario
• 412 Vario
• 711 Vario
• 712 Vario
• 714 Vario
• 715 Vario
• 716 Vario
• 717 Vario
• 718 Vario
• 916 Vario
• 920 Vario
• 924 Vario
• 926 Vario
• 930 Vario
• Farmer 400 Vario
• Favorit 700 Vario
• Favorit 900 Vario
• Fendt 200 Vario Series
• Fendt 300 Vario Series
• Fendt 400 Vario Series
• Fendt 500 Vario Series
• Fendt 700 Vario Series
• Fendt 800 Vario Series
• Fendt 900 Vario Series
• Fendt 1000 Vario Series

1. 1

   Check transmission oil level and inspect the filter contamination switch (S017) to rule out a clogged filter or fluid starvation.

2. 2

   Test the electrical supply and resistance of the speed range control solenoids (Y001, Y002, Y003).

3. 3

   Inspect the wiring harness and cable couplers connecting the transmission control unit to the Y001 and Y002 solenoids for continuity, shorts to ground, or supply failures.

4. 4

   Check the travel range detection sensor (B016) to ensure it is not sending illogical position data to the ECU.

1. 1

   Preparation

   Safely park the tractor, turn off the engine, and relieve any residual hydraulic pressure.

2. 2

   Valve Unit Removal

   Disconnect the cable couplers and hydraulic lines from the transmission control valve unit. Remove the fastening screws and carefully extract the valve unit.

3. 3

   Installation of New Components

   Screw two M8 stud bolts into the transmission housing to act as guides. Fit a new gasket to the mating surface. Lubricate the new O-rings with a small amount of grease and fit them into the new/repaired valve unit.

4. 4

   Reassembly

   Insert the valve unit over the stud bolts. Tighten the fastening screws to 25 Nm, working from the inside to the outside. Reconnect all hydraulic lines and electrical cable couplers.

5. 5

   Fluid Top-Up

   If fluid was lost, top up the transmission with approved STOU SAE 5W-30, 5W-40, 10W-30, 10W-40, 15W-30, or 15W-40 oil.

6. 6

   EOL Reprogramming

   Perform EOL (End of Line) reprogramming using the FENDIAS diagnostic tool to recalibrate the shift tolerances and clear the fatal error state.