Fendt A.1.56 – A057 - ECU, steering controller (Auto-Guide): An EEPROM reading fault has occurred.

The steering controller's internal memory (EEPROM) has failed to read its stored data or parameters. This is an internal logic/memory error within the control unit.

• 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 300 Vario COM III series
• Fendt 400 Vario COM III series
• 411
• 412
• 413
• 414
• 415
• Fendt 700 Vario COM III series
• 712
• 714
• 716
• 718
• Fendt 800 Vario COM III series
• 820 Vario greentec
• Fendt 900 Vario COM III series

1. 1

   Verify the A057 ECU is receiving proper and stable voltage, as low voltage or power spikes can cause temporary EEPROM read/write errors.

2. 2

   Check software and calibration by attempting EOL (End-Of-Line) programming using the FENDIAS dealer diagnostic tool to re-flash the EEPROM data.

1. 1

   Connect diagnostic tool

   Connect the FENDIAS diagnostic laptop to the tractor's diagnostic port.

2. 2

   Navigate to module

   Navigate to the A057 Steering Controller module.

3. 3

   Execute EOL programming

   Execute the EOL programming procedure to rewrite the EEPROM parameters.

4. 4

   Clear codes and cycle ignition

   Clear the fault codes and cycle the tractor's ignition.

5. 5

   Test system

   Test the Auto-Guide system. If the A.1.56 fault code returns, replace the box, as the EEPROM chip has suffered a permanent hardware failure.

6. 6

   Replace A057 ECU

   If replacement is necessary, physically locate the A057 ECU, disconnect the wiring harnesses, and swap in the new module.

7. 7

   Calibrate new ECU

   Perform EOL programming and steering angle sensor (WAS) calibration on the newly installed A057 ECU so it can communicate with the tractor's CAN bus.