Fendt A.1.70 – A002 - ECU, Enhanced Control: B094 - Sensor, steering angle (4WD differential lock)

Break in steering sensor signal line causing the 4WD and differential lock auto systems to become inoperable.

• 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)
• Fendt 400 Vario (COM III) (e.g., Farmer 409, 410, 411, 412)
• Fendt 700 Vario (COM III) (e.g., 712, 714, 716, 718)
• Fendt 800 Vario (COM III) (e.g., 815, 817, 818, 820)
• Fendt 900 Vario (COM III)
• Fendt Katana 65 Forage Harvester

1. 1

   Inspect the wiring harness connecting the B094 sensor on the front axle to the A002 ECU for visible damage, chafing, or broken wires.

2. 2

   Consult electrical wiring diagram Sheet 33 / 39 to trace the exact pinouts for the signal line.

3. 3

   Test sensor contacts for proper continuity and resistance (Pins 1, 3, and 4 are responsible for 4WD/differential lock; Pins 2, 3, and 5 are for Autoguide).

1. 1

   Locate the Sensor

   Find the B094 steering angle sensor mounted on the front axle bridge.

2. 2

   Inspect and Repair Wiring

   If the diagnostic continuity test reveals a broken wire in the harness between the sensor and the ECU, repair the wiring harness.

3. 3

   Replace the Sensor

   If the wiring is fully intact and the signal line break is internal to the sensor, the B094 sensor must be replaced.

4. 4

   Removal

   Disconnect the electrical connector from the sensor. Unbolt the sensor from its mounting bracket on the axle universal joint.

5. 5

   Installation

   Mount the new OEM steering angle sensor and secure the bolts. Reconnect the wiring harness.

6. 6

   Clear Codes

   Use the FENDIAS diagnostic tool or the tractor's onboard terminal to clear the stored A.1.70 fault code from the memory.

7. 7

   Calibration

   Perform a steering angle sensor calibration (often required after replacing axle sensors so the ECU learns the new center, left-lock, and right-lock values).