Fendt 18.1.2C – A050 - ECU, basic control unit: B081 - Steering wheel sensor (360°) - Invalid calibration values for steering wheel sensor in EEPROM.

The tractor's control system has lost the calibration data for the steering wheel sensor, or the stored values in the EEPROM are corrupted/invalid. This sensor is primarily used to detect when the operator manually turns the steering wheel so the system can automatically disengage the VarioGuide / Auto-Guide automatic track guidance.

• 922 Vario COM III
• 924 Vario COM III
• 927 Vario COM III
• 930 Vario COM III
• 933 Vario COM III
• 936 Vario COM III
• Fendt 300 Vario (COM III)
• Fendt 400 Vario (COM III)
• Fendt 700 Vario (COM III and SCR / Tier 3b)
• Fendt 800 Vario (COM III and S4)
• Fendt 900 Vario (COM III, SCR, and S4 generations, including models 922, 924, 927, 930, 933, 936, and 939)

1. 1

   Verify the 12V power supply to the B081 sensor (powered via the A013 module, fuse 29)

2. 2

   Inspect the wiring harness and connections between the B081 steering wheel sensor and the A050 Basic Control Unit for breaks, corrosion, or loose pins

3. 3

   Use the tractor's diagnostic terminal to monitor the signal value of the B081 sensor to ensure the signal is not faulty or missing

1. 1

   Ensure preliminary conditions are satisfied

   Ensure all preliminary conditions for calibration are satisfied (e.g., tractor stationary, engine running or ignition on as specified by the terminal).

2. 2

   Access diagnostic system

   Access the tractor's diagnostic system (via the MFA terminal or FENDIAS software).

3. 3

   Initiate calibration

   Initiate the calibration procedure for the steering wheel sensor. The specific calibration codes for the B081 sensor are "2401" or "2403".

4. 4

   Complete calibration

   Follow the on-screen prompts to complete the 360° rotation calibration.

5. 5

   Replace sensor if calibration fails

   If the calibration fails (the system may throw secondary codes like F02 "Calibrated values are faulty" or F08 "Calibration taking too long"), the B081 sensor is likely defective and must be physically replaced.

6. 6

   Install new sensor and recalibrate

   If replacement is necessary, install the new B081 sensor on the steering column and repeat the calibration process (code 2401 or 2403) to write the new sensor's values to the A050 ECU's EEPROM.