Fendt 4.1.B5 – A002 - ECU, enhanced control: Checksum error ramp parameter, rapid reverse for Tractor Management System (TMS)

The control module has detected a checksum error in its EPROM programming specifically related to the rapid reverse ramp parameters. Because the stored parameters are corrupted or incorrect, the Tractor Management System (TMS) cannot validate the data required to execute a rapid reverse maneuver smoothly. Rapid reversing is either not operational within the TMS, or the tractor defaults to standard (factory default) values to allow rapid reversing in a limited capacity. The tractor can typically still be driven.

• 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 series
• Fendt Favorit 700 and 900 series
• Fendt 300 Vario (including COM III)
• Fendt 400 Vario (including COM III)
• Fendt 700 Vario (including COM III)
• Fendt 800 Vario (including COM III)
• Fendt 900 Vario (including COM II and COM III)

1. 1

   Test drive the tractor to confirm if the rapid reverse function is completely inoperative or if it is functioning using harsh/standard default values

2. 2

   Use the Variotronic TI terminal (A008) to check for other CAN bus communication errors

3. 3

   If the A002 ECU has lost communication entirely, check the voltage supply to the CAN-Bus on fuse board A013 (specifically fuses F040 and F041)

4. 4

   Through the Variotronic diagnostics menu, check the load counter of the A002 ECU (if unloaded, a value of around 22000 is indicated; if loading is increasing, a lower value is shown)

1. 1

   Connect diagnostic system

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

2. 2

   Perform EOL programming

   Perform an EOL (End-Of-Line) programming on the A002 ECU. This will overwrite the corrupted EPROM data and reload the correct rapid reverse ramp parameters for the specific tractor chassis.

3. 3

   Clear fault codes

   Clear the stored fault codes via FENDIAS.

4. 4

   Test operation

   Test the rapid reverse function to ensure the TMS is operating smoothly.

5. 5

   Replace hardware

   If the EOL programming fails to write, or if the EPROM cannot be overwritten (note: some older E-boxes require physical EPROM replacement rather than a flash update), the A002 E-Box must be replaced or sent out for board-level repair.