Fendt 4.1.B3 – A002 - ECU, enhanced control: A002 - ECU, enhanced control — Fault in EPROM programming (rapid reversing ramp parameters)

This fault indicates a memory/programming error within the control unit's EPROM. Specifically, the custom calibration parameters for the 'rapid reversing ramp' (how aggressively the tractor changes direction) have been corrupted or lost. Because the custom parameters are unavailable, the system defaults to standard/safe values.

• 409 Vario
• 410 Vario
• 411 Vario
• 412 Vario
• 711 Vario
• 712 Vario
• 714 Vario
• 715 Vario
• 716 Vario
• 717 Vario
• 718 Vario
• 916 Vario
• 920 Vario
• 924 Vario
• 926 Vario
• 930 Vario
• 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 (409, 410, 411, 412)
• Fendt Favorit 700 Vario (711, 712, 714, 716)
• Fendt Favorit 900 Vario (916, 920, 924, 926, 930)
• Fendt 300 Vario series
• Fendt 400 Vario series
• Fendt 700 Vario series
• Fendt 800 Vario series
• Fendt 900 Vario series
• Fendt 300 Vario series COM III
• Fendt 400 Vario series COM III
• Fendt 700 Vario series COM III
• Fendt 800 Vario series COM III
• Fendt 900 Vario series COM III

1. 1

   Verify operation to confirm the tractor can still drive and perform rapid reversing using standard default values.

2. 2

   Check the CAN-Bus voltage supply on fuse board A013 (specifically fuses F040 and F041) to ensure the A002 ECU is receiving stable voltage, as drops or spikes can corrupt EPROM memory.

3. 3

   Connect the Fendt EST (FENDIAS) diagnostic software to verify communication with the A002 module on the K-bus/G-bus.

1. 1

   Connect Diagnostic Tool

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

2. 2

   Perform EOL Reprogramming

   Perform an End-Of-Line (EOL) programming procedure on the A002 ECU to re-flash the correct rapid reversing ramp parameters into the EPROM.

3. 3

   Clear Codes

   Once the EOL programming is complete, clear the fault codes from the system.

4. 4

   Test Operation

   Test drive the tractor and perform rapid reversing maneuvers to ensure the parameters hold and the fault code does not return.

5. 5

   Module Replacement (If Necessary)

   If the FENDIAS tool cannot write to the EPROM, or if the code returns immediately after a battery cycle, the physical memory chip inside the A002 ECU has failed. The A002 module will need to be replaced and subsequently EOL programmed to the specific tractor chassis.