Fendt 04.1.20 – A039 or A100 (MFA, Multifunction Armrest): EEPROM checksum incorrect or not calibrated

EEPROM checksum incorrect or not calibrated relating to the throttle pedal resolution potentiometer (slide switch). Throttle pedal mode is not possible, and the TMS (Tractor Management System) is automatically switched off.

• 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 400 Vario series (411, 412, 413, 414, 415)
• Fendt 700 Vario series
• Fendt 800 Vario series
• Fendt 900 Vario series (COM III, S4, etc.)

1. 1

   Verify the tractor is parked safely, the hand brake is applied, and the transmission is in neutral

2. 2

   Inspect the physical condition of the throttle pedal resolution potentiometer (slide switch) on the multifunction armrest for physical damage, debris, or sticking

3. 3

   Check for related signal fault codes (such as 04.1.22). If present, the component is likely faulty and calibration will fail

1. 1

   Turn the ignition ON (engine off).

   Ensure the engine is not running.

2. 2

   Ensure the hand brake is applied and the transmission is in neutral.

   Safety prerequisite for calibration.

3. 3

   Access the tractor's terminal/dashboard diagnostic menu.

   Navigate to the diagnostic section on the terminal.

4. 4

   Enter the specific calibration code for the accelerator pedal resolution: 4010.

   Input code 4010 to initiate calibration.

5. 5

   Follow the on-screen prompts on the terminal to calibrate the slide switch/potentiometer.

   Complete the calibration sequence as directed by the terminal.

6. 6

   Once the calibration process is complete, cycle the ignition.

   Wait at least 15 seconds before switching the ignition back on.

7. 7

   Clear the fault codes from the memory and test the throttle pedal and TMS engagement.

   Verify that the accelerator mode works and TMS engages properly.

8. 8

   Replace or repair the potentiometer or MFA control unit if calibration fails.

   If the terminal displays an 'ERROR' message during calibration, or if the fault code immediately returns, the component has suffered a hardware failure.