Fendt 06.1.C0 – A050 - ECU, basic control unit: Warning: 540 stub shaft at rate 1000

A safety mismatch warning triggered when the tractor's sensors detect that the 540 RPM stub shaft (typically a 6-spline shaft) is physically installed on the tractor, but the operator has selected the 1000 RPM or 1000E RPM PTO speed range in the cab. This prevents the operator from accidentally overspeeding a 540 RPM implement.

• 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 and SCR models)
• Fendt 800 Vario (COM III and SCR models)
• Fendt 900 Vario (COM III and SCR models)

1. 1

   Verify the Installed Stub Shaft: Physically inspect the rear PTO stub shaft. A 540 RPM setup uses a 1 3/8" 6-spline shaft, while a 1000 RPM setup uses a 1 3/8" 21-spline or 1 3/4" 20-spline shaft.

2. 2

   Check Cab Settings: Verify the PTO speed preselection on the terminal/controls. If 1000 RPM is selected while a 6-spline shaft is installed, the system is operating exactly as designed to prevent damage.

3. 3

   Sensor Inspection: If the correct 1000 RPM stub shaft is installed but the code persists, the issue lies in the detection circuit. Inspect the B020 - rear PTO stub shaft speed sensor (and its separation point X169/X170) for damage, debris, or wiring faults leading back to the A050 ECU.

1. 1

   Safety First

   Shut off the engine and remove the ignition key. Ensure the PTO shaft has come to an absolute stop.

2. 2

   Remove the Old Shaft

   Release and remove the hex bolts securing the current 540 RPM PTO shaft stub.

3. 3

   Clean the Mating Surfaces

   Thoroughly clean the screw-on face on the tractor and the mounting face of the new 1000 RPM PTO shaft stub.

4. 4

   Install the New Shaft

   Fit the 1000 RPM stub shaft, ensuring that the stub is seated correctly and the identification cam profile is properly aligned with the detection mechanism.

5. 5

   Torque to Spec

   Evenly tighten the M12 (12.9 grade) retaining screws to 110 Nm.

6. 6

   Clear Codes

   Turn the tractor back on and verify that the 1000 RPM speed can now be selected without triggering the 06.1.C0 warning. (Note: If the correct shaft was already installed, the B020 stub shaft sensor or its wiring harness must be replaced).