Fendt 6.1.60 – Rear PTO Control System: Plausibility error between PTO clutch rpm and PTO stub shaft speed

The actual speed of the PTO stub shaft (corrected by the transmission rate) differs from the specified setpoint speed of the PTO clutch by more than ±12%. The PTO will not function normally and will disengage. Emergency mode allows electric speed selection if the operator presses and holds the 'Engage PTO' key for more than 5 seconds.

• 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 409
• Farmer 400 Vario 410
• Farmer 400 Vario 411
• Farmer 400 Vario 412
• Favorit 700 Vario 711
• Favorit 700 Vario 712
• Favorit 700 Vario 714
• Favorit 700 Vario 715
• Favorit 700 Vario 716
• Favorit 700 Vario 717
• Favorit 900 Vario 916
• Favorit 900 Vario 920
• Favorit 900 Vario 924
• Favorit 900 Vario 926
• Favorit 900 Vario 930
• Favorit 900 Vario 936
• 800 Vario 815
• 800 Vario 817
• 800 Vario 818
• 800 Vario 820
• Other Vario COM III models

1. 1

   Test the signal output of the B020 (stub shaft) and B021 (clutch) Hall-effect speed sensors

2. 2

   Inspect the PTO speed selection solenoid valves (Y026, Y027, Y028) for incorrect wiring or mechanical seizing

3. 3

   Check the mechanical speed selector mechanism for physical faults, binding, or damage preventing synchronization

1. 1

   Access the Sensors

   Locate the B020 and B021 Hall-effect sensors at the rear of the tractor (B020 is on the PTO stub shaft, B021 is at the PTO clutch).

2. 2

   Inspect Wiring

   Check the wiring harnesses and separation points (e.g., connector X169 for B020 and X170 for B021) for corrosion, breaks, or loose pins. Repair any damaged wiring.

3. 3

   Test/Replace Sensors

   If the wiring is intact but the plausibility error persists, test the sensors with a multimeter/oscilloscope. Replace B020, B021, or both if they fail to output a clean speed signal.

4. 4

   Service Solenoid Valves

   Locate solenoid valves Y026, Y027, and Y028. Apply direct voltage to test their actuation. If a valve is seized, remove it, clean the hydraulic passages, and replace the valve if it remains stuck.

5. 5

   Clear Codes

   Use the tractor's diagnostic terminal to confirm and delete the stored fault code from memory.

6. 6

   Operational Test

   Run the tractor and engage the PTO normally to ensure the speeds synchronize within the 12% threshold and the PTO no longer disengages.