Fendt 6.1.B8 – A004 - Control Console / Control Panel (ECU): 1000 rpm speed selector key — Communication fault.

This fault indicates a communication error or signal fault originating from the 1000 rpm rear PTO speed selector key/button. The system detects that the signal from the key is missing, faulty, or mechanically stuck (e.g., pressed for more than 30 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
• 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
• Fendt Farmer 400 series
• Fendt Favorit 700 series
• Fendt Favorit 900 series (chassis number 23/3001 and up)
• Fendt 300 Vario (COM III)
• Fendt 400 Vario (COM III)
• Fendt 700 Vario (COM III)
• Fendt 800 Vario (COM III)
• Fendt 900 Vario (COM III)

1. 1

   Inspect the 1000 rpm speed selector key on the A004 control console. Check if the button is physically stuck, jammed by debris, or held down (the system flags an error if the key is pressed for more than 30 seconds).

2. 2

   Consult the PTO's circuit diagram to trace the wiring from the 1000 rpm key to the A004 control panel. Test for continuity, shorts to ground, or open circuits.

3. 3

   If the entire A004 control console is unresponsive (no display/functions), check the CAN bus voltage supply on fuse board A013. Specifically, inspect fuses F040 and F041.

4. 4

   Connect the FENDIAS diagnostic tool to verify if the A004 module is communicating with the rest of the tractor's CAN bus network.

1. 1

   Disconnect Power

   Turn off the tractor and disconnect the battery to prevent electrical shorts during the repair.

2. 2

   Free the Switch

   If the diagnostic check revealed a mechanically stuck 1000 rpm button, carefully clean the area around the switch on the control console. If it pops back into place and tests fine, no parts replacement is necessary.

3. 3

   Check Fuses

   If the A004 console lacks power, locate fuse board A013 and replace fuses F040 or F041 if blown.

4. 4

   Replace the Switch/Console

   If the wiring is intact but the switch has an internal electrical failure, replace the 1000 rpm PTO speed selector switch. Depending on the specific console revision, this may require replacing the individual switch module or the larger A004 control console keypad assembly.

5. 5

   Clear Codes

   Reconnect the battery, power on the tractor, and use the FENDIAS system to clear the 6.1.B8 fault code. Test the PTO engagement to ensure the 1000 rpm speed can now be selected.