Fendt 08.1.A0 – A024 - ECU, EPC B: Checksum incorrect / EEPROM error when saving

A memory/software corruption issue where the control module's internal memory (EEPROM) has failed to save data correctly, resulting in a mismatched checksum. As a consequence, the rear power lift (electrohydraulic lifting gear) will lock, move to neutral, or cease to function in automatic mode.

• 309 Vario COM III
• 310 Vario COM III
• 311 Vario COM III
• 312 Vario COM III
• Fendt 200 V/F/P Vario series
• Fendt 300 Vario (COM III) series
• Fendt 400 Vario series
• Fendt 700 Vario series
• Fendt 800 Vario series
• Fendt 900 Vario series

1. 1

   Test external actuation by checking if the rear lift functions using the external fender buttons (manual actuation may still work even if automatic mode is locked out).

2. 2

   Check system voltage to verify the charging system is operating within the normal 12-14.5V range, as voltage spikes (e.g., > 18V) can cause EEPROM saving errors.

3. 3

   Read extended fault data using the FENDIAS diagnostic tool to confirm the specific byte address of the checksum error and rule out a wiring short.

1. 1

   Connect Diagnostic Tool

   Connect the FENDIAS (Fendt Diagnostic System) laptop to the tractor's diagnostic port.

2. 2

   Perform EOL Programming

   Run a new EOL (End of Line) programming sequence specifically for the A024 - ECU, EPC B. This rewrites the EEPROM and corrects the checksum mismatch.

3. 3

   Recalibrate Sensors

   After EOL programming, recalibrate the rear power lift position sensor (B030) and the setpoint rotary switch (A035), as their calibration data may have been wiped during the EEPROM error or the re-flash.

4. 4

   Module Replacement

   If the FENDIAS tool cannot communicate with the A024 ECU, if the EOL programming fails, or if the 08.1.A0 code immediately returns after a successful flash, the EEPROM chip inside the ECU has physically failed. The A024 EPC B control box must be replaced or sent to an agricultural electronics specialist for internal board repair.