Fendt 04.1.E3 – A050 - ECU, basic control unit / A002 - ECU, enhanced control: Checksum error, parameter for throttle pedal mode

A software or memory error where the control unit detects that the stored calibration parameters or mapping data for the foot throttle pedal are corrupted or invalid. The tractor will default to Emergency mode and the TMS (Tractor Management System) is switched off.

• 309 Vario COM III
• 310 Vario COM III
• 311 Vario COM III
• 312 Vario COM III
• Fendt 300 Vario
• Fendt 400 Vario
• Fendt 700 Vario
• Fendt 800 Vario
• Fendt 900 Vario (e.g., 916, 920, 924, 926, 930, 936)

1. 1

   Verify the B055 Foot Throttle Sensor: Ensure the sensor is functioning and that the signals match. Potentiometer 1 sends an analog voltage signal to the A050 basic control unit, while Potentiometer 2 sends a signal to the A051 engine control unit (EDC).

2. 2

   Check Power Supply: Verify the voltage supply to the throttle pedal sensor, which is powered by the A013 PCB microfuses.

3. 3

   Check for Accompanying Codes: Look for related B055 sensor codes (such as 01.1.01 or 01.1.03) which indicate physical signal loss, shorts, or lack of congruence between the two potentiometers. If these are present, the sensor or wiring is the root cause rather than the ECU memory.

1. 1

   Connect diagnostic interface

   Connect the Fendt diagnostic interface (FENDIAS / EST) to the tractor.

2. 2

   Perform EOL programming

   Perform EOL (End-of-Line) programming on the A050 / A002 control unit. This rewrites the correct parameters and mapping fields for the throttle pedal mode into the ECU's memory.

3. 3

   Recalibrate foot throttle pedal

   Following the EOL programming, recalibrate the foot throttle pedal (using calibration code 4005 or 4010, depending on the specific model).

4. 4

   Clear fault codes

   Clear the stored fault codes from the memory.

5. 5

   Restart and verify

   Restart the tractor and verify that TMS functionality is restored and the tractor is no longer in emergency mode.

6. 6

   Repair or replace ECU

   If the EOL programming fails to write, or the checksum error immediately returns, the A050/A002 ECU has suffered an internal EEPROM hardware failure and must be repaired or replaced.