Fendt 4.1.F0 – A002 - ECU, enhanced control: Incorrect checksum for transmission calibration parameters

This is a software/memory error indicating that the stored calibration values for the transmission have become corrupted or mismatched in the module's EEPROM/RAM. As a direct consequence of this fault, the tractor will block any attempts to perform a transmission calibration.

• 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 Vario series
• Fendt Favorit 700 / 700 Vario series (COM II / COM III)
• Fendt Favorit 900 / 900 Vario series (COM II / COM III)
• Fendt 800 Vario series

1. 1

   Verify the code on the tractor's diagnostic terminal to confirm 4.1.F0 is active

2. 2

   Attempt to initiate the transmission calibration routine to see if the system rejects the calibration attempt

3. 3

   Verify the basic signal voltage and CAN-bus communication to the A002 ECU (should have a basic signal voltage of 8.0V on COM II/III systems)

1. 1

   Connect diagnostic software

   Connect the tractor to the FENDIAS diagnostic software interface.

2. 2

   Perform EOL programming

   Perform EOL (End-Of-Line) programming on the A002 ECU. This process reflashes the control unit and rewrites the standard parameters to clear the corrupted memory.

3. 3

   Perform transmission calibration

   Once the EOL programming is successfully completed, initiate and complete a full transmission calibration.

4. 4

   Replace or repair ECU

   If the A002 ECU fails to accept the EOL programming, or if the 4.1.F0 checksum error immediately returns after flashing, the internal EEPROM/RAM has physically failed. The A002 ECU must be removed and either sent to an agricultural electronics specialist for board repair or replaced entirely.