Fendt 6.1.43 – Enhanced Control ECU (A002): Left external "Rear PTO ON / OFF" pushbutton pressed continuously

The Left external "Rear PTO ON / OFF" pushbutton (located on the rear fender) has been registered as being pressed continuously for more than 30 seconds. This indicates a mechanical fault (jammed/stuck button) or an electrical fault (short circuit). As a safety consequence, the tractor disables PTO speed selection, and the PTO cannot be engaged normally.

• 411 Vario COM III
• 412 Vario COM III
• 413 Vario COM III
• 414 Vario COM III
• 415 Vario COM III
• 712 Vario COM III
• 714 Vario COM III
• 716 Vario COM III
• 718 Vario COM III
• 818 Vario COM III
• 820 Vario COM III
• Farmer 400 Vario Series (409, 410, 411, 412)
• Favorit 700 Vario Series (711, 712, 714, 716)
• Favorit 900 Vario Series (916, 920, 924, 926, 930)
• Fendt 300 Vario Series
• Fendt 700 Vario Series
• Fendt 800 Vario Series
• Fendt 900 Vario Series

1. 1

   Check the left external rear PTO button on the rear fender for physical damage, packed dirt, or debris causing it to stick.

2. 2

   Press and release the button to verify it has a normal spring return.

3. 3

   Inspect the wiring harness and plug connection at the back of the switch for corrosion, moisture ingress, or rubbed wires causing a short to ground.

4. 4

   Use a multimeter to test the switch for continuity. It should only close the circuit when actively pressed; if it shows continuity when released, the internal contacts have failed.

1. 1

   Disconnect Power

   Disconnect the tractor's battery to ensure electrical safety before working on the circuit.

2. 2

   Access the Switch

   Access the rear left fender where the external PTO switch is mounted.

3. 3

   Disconnect Wiring

   Unplug the electrical connection from the back of the faulty switch. Depending on the model year, this will either be a sealed AMP Superseal plug (3 x 1.5) or a 7-blade terminal block.

4. 4

   Remove the Switch

   Remove the retaining nut or clips holding the 30mm switch body in the fender panel and pull the old switch out.

5. 5

   Install the New Part

   Insert the new switch into the 30mm mounting hole and secure it tightly.

6. 6

   Reconnect

   Reconnect the electrical wiring harness to the new switch. Ensure the weather-sealed connection is seated properly to prevent future moisture and dust ingress.

7. 7

   Test

   Reconnect the battery. Test the PTO engagement from both the in-cab controls and the new external fender switch to confirm the fault code is cleared and normal functionality is restored.