Fendt 06.1.50 – REAR PTO ENHANCED CONTROL: B020 - Sensor, rear PTO speed (stub shaft)

This code indicates a signal fault or plausibility error originating from the Hall-effect speed sensor (B020) located on the rear PTO stub shaft. The system detects that the PTO stub shaft speed is reading greater than 1300 rpm, or the actual speed of the stub shaft differs by more than ±12% from the setpoint speed of the PTO clutch (monitored by sensor B021). The tractor defaults to an emergency operating mode where the PTO will not engage normally unless the operator presses and holds the 'Engage PTO' button for at least 5 seconds.

• 309 Vario COM III
• 310 Vario COM III
• 311 Vario COM III
• 312 Vario COM III
• 922 Vario COM III
• 924 Vario COM III
• 927 Vario COM III
• 930 Vario COM III
• 933 Vario COM III
• 936 Vario COM III
• 200 Vario Series
• 300 Vario (COM III) Series
• 400 Vario (COM III) Series
• 409
• 410
• 411
• 412
• 700 Vario (COM III) / Favorit 700 Series
• 711
• 712
• 714
• 716
• 800 Vario (COM III) Series
• 815
• 817
• 818
• 820
• 900 Vario (COM III / S4 / SCR) / Favorit 900 Series
• 916
• 920
• 922
• 924
• 926
• 927
• 930
• 933
• 936
• 939

1. 1

   Check Power Supply: Verify the 12V power supply to the B020 Hall-effect sensor. Check the integrity of Fuse 35 (A013), which supplies power to this circuit.

2. 2

   Inspect Wiring: Inspect the wiring harness and connectors (specifically connector X169) leading to the B020 sensor for chafing, open circuits, shorts to ground, or corrosion.

3. 3

   Compare Sensors: Verify that the PTO clutch speed sensor (B021) is functioning correctly and not providing a false baseline.

4. 4

   Check Solenoid Valves: Inspect the PTO speed selection solenoid valves (Y026, Y027, Y028). Ensure they are not wrongly wired, mechanically seized, or stuck in the 'OFF' position.

1. 1

   Preparation

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and remove the key.

2. 2

   Locate the Sensor

   Locate the B020 Hall-effect speed sensor on the rear PTO stub shaft assembly at the rear axle housing.

3. 3

   Electrical Disconnect

   Disconnect the electrical harness from the B020 sensor. Use a multimeter with the ignition ON to confirm 12V power and a solid ground at the connector.

4. 4

   Remove the Sensor

   Clean the area around the sensor to prevent dirt from entering the housing. Remove the retaining bolt holding the B020 sensor. Carefully pull the sensor out (have a rag or catch pan ready, as a small amount of transmission/hydraulic oil may seep out).

5. 5

   Install the New Sensor

   Lubricate the O-ring on the new sensor with clean transmission oil. Insert it into the housing and tighten the retaining bolt to the OEM specified torque.

6. 6

   Reassembly

   Reconnect the electrical harness, ensuring the connector clicks securely into place.

7. 7

   Clear Codes & Test

   Turn on the tractor ignition, access the Fendt Varioterminal diagnostics menu, and clear the stored 06.1.50 fault code. Start the tractor and engage the rear PTO normally (without holding the button for 5 seconds) to verify the repair.