Fendt 0A.1.B9 – A039 or A100: Linear module 2 (rocker switch) faulty or engaged at ignition

Linear module 2 (rocker switch/rocker pair) is faulty or was physically engaged/pressed when the ignition was switched on. The valve position is not functioning, and the system locks the valve for safety.

• 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 200 V/F/P Vario
• Fendt 300 Vario (COM III)
• Fendt 400 Vario (COM III)
• Fendt 700 Vario (COM III and SCR models)
• Fendt 800 Vario (COM III and S4 models)
• Fendt 900 Vario (COM III and SCR models)

1. 1

   Check if the linear module 2 (rocker switch) on the multifunction armrest is physically stuck, jammed by debris, or accidentally being pressed by the operator when the ignition is turned on.

2. 2

   Check if the linear module has lost its calibration (calibration code 1004). A related code (like 0A.1.BA) indicates the module is not calibrated.

3. 3

   Test the MFA (A039 or A100) using the Fendt 160-pin adapter box to verify if the module is sending the correct signals to the central electrical system.

1. 1

   Clear the Switch

   Ensure the rocker switch (linear module 2) is in the neutral position and free of any physical obstructions. Turn the ignition off and back on without touching the armrest controls.

2. 2

   Calibrate the Module

   Access the tractor's terminal transmission/calibration menu. Enter calibration code 1004 to recalibrate linear module 2 (hydraulic auxiliary control valve).

3. 3

   Replace the Module/Armrest

   If the rocker switch is internally shorted, mechanically broken, or fails calibration, the linear module (or the armrest console section) must be replaced.

4. 4

   Clear Fault Codes

   After repair, clear the fault codes. On some models, you can call up the fault code on the instrument panel (A007) and press buttons A, B, and C (both arrow keys) simultaneously to delete it. Faults stored in the basic control unit (A050) may require FENDIAS diagnostic software to clear.