Fendt 6.1.57 – A004 - ECU, control panel: 750 rpm speed selector key has been pressed for more than 30 seconds, mechanical or electrical fault in key.

The system has detected that the button used to select the 750 rpm (or 540E) rear PTO speed is stuck in the closed (pressed) position for an abnormal amount of time (>30 seconds).

• 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
• Favorit 700 Vario
• Favorit 900 Vario
• Fendt 300 Vario series
• Fendt 400 Vario series
• Fendt 700 Vario series
• Fendt 800 Vario series
• Fendt 900 Vario series

1. 1

   Inspect the 750 rpm / 540E button on the A004 operating console for physical damage, sticky residue, or debris, and verify it springs back normally.

2. 2

   Disconnect the battery and use a multimeter to test the continuity of the switch (it should only show continuity when actively pressed).

3. 3

   Consult the wiring diagram and trace the signal wire from the switch to the A004 control panel to ensure the wire is not shorted to ground or voltage.

1. 1

   Power Down

   Turn off the ignition and disconnect the tractor's battery to prevent electrical spikes.

2. 2

   Clean the Switch

   If the button is mechanically sticking due to dirt, spray a plastic-safe electronic contact cleaner around the edges of the button and actuate it repeatedly to free it up. Blow out any remaining debris with compressed air.

3. 3

   Access the Console

   If cleaning does not resolve the stuck circuit, carefully remove the trim panels surrounding the A004 operating console to access the switch wiring and mounting hardware.

4. 4

   Replace the Component

   If the 750 rpm switch is a modular, plug-and-play component, disconnect its harness, pop the faulty switch out of the bezel, and snap the new one into place. If the switch is integrated directly into the A004 control panel circuit board, the entire A004 control panel assembly must be replaced.

5. 5

   Reassembly & Testing

   Reconnect the battery and turn on the ignition. Use the tractor's terminal or FENDIAS diagnostic software to clear the stored 6.1.57 fault code.

6. 6

   Verify Operation

   Cycle through the 540, 750 (540E), and 1000 rpm PTO speeds to ensure they select normally and the fault does not return.