Fendt 04.1.E1 – A002 / A050: Traction control regulator parameters (ML transmission adjustment) are not plausible or read incorrectly

When this fault is triggered, the tractor's transmission will typically default to Emergency Mode.

• 309 Vario COM III
• 310 Vario COM III
• 311 Vario COM III
• 312 Vario COM III
• Fendt 300 Vario (COM III)
• Fendt 400 Vario (COM III) & Farmer 400
• Fendt 700 Vario (COM III) & Favorit 700
• Fendt 800 Vario (COM III)
• Fendt 900 Vario (COM III) & Favorit 900

1. 1

   Verify Emergency Mode: Confirm the tractor is operating in emergency mode, which limits transmission functionality.

2. 2

   Check CAN Bus Communication: Ensure the A002/A050 module is communicating properly on the CAN bus (both G-bus and K-bus).

3. 3

   Check for Accompanying Codes: Look for related checksum or EPROM fault codes (e.g., 04.1.E2, 04.1.B2, 04.1.B3) which indicate broader memory or programming corruption within the ECU.

1. 1

   Connect Diagnostic Tool

   Connect the Fendt FENDIAS diagnostic system to the tractor.

2. 2

   Perform EOL Programming

   The official remedy for code 04.1.E1 is EOL (End of Line) programming. You must re-flash or re-calibrate the traction control regulator parameters for the ML transmission adjustment.

3. 3

   Test the Module

   If EOL programming fails to write, or the parameters immediately corrupt again, the A002/A050 Basic Control Unit has suffered an internal EPROM/memory failure.

4. 4

   Module Repair/Replacement

   If the module is defective, remove the A050/A002 Basic Control Unit. It must either be sent to an agricultural electronics specialist for board-level repair or replaced with a new OEM unit.

5. 5

   Post-Repair Calibration

   If a new or repaired module is installed, a full EOL programming sequence must be performed to marry the module to the tractor's specific transmission.