Fendt 00.1.AA – Instrument Cluster / Dashpanel: Sensor, compressed air supply / Compressed air tank pressure sensor

Sensor failure, signal fault, or wiring failure (such as a 12V supply fault). When this fault is active, the system loses its ability to monitor the air brake circuit's storage tank pressure, and the compressed air indicator on the dashboard will typically fail to function or display a reading. On tractors with a 2-circuit brake system, a perceived drop in pressure (below 4.6 bar) may cause the 4WD to permanently activate as a safety measure.

• 922 Vario COM III
• 924 Vario COM III
• 927 Vario COM III
• 930 Vario COM III
• 933 Vario COM III
• 936 Vario COM III
• 309
• 310
• 311
• 312
• 409
• 410
• 411
• 412
• 711
• 712
• 714
• 716
• 815
• 817
• 818
• 916
• 920
• 924
• 926
• 930
• 933
• 936
• 939

1. 1

   Verify dashboard symptoms by confirming that the compressed air indicator is blank or non-functional.

2. 2

   Perform a manual pressure test using a mechanical pressure gauge to verify the actual pressure in the compressed air storage tank (normal operating pressure is typically around 8.1 bar). This rules out a failing air compressor or a massive system leak.

3. 3

   Inspect the wiring harness and connector at the B019 sensor (mounted on the air tank) for broken wires, corrosion, or a short circuit.

4. 4

   Test the connector for a proper 12V reference supply from the instrument cluster. If voltage is missing, trace the circuit diagram for the dashpanel to find the break.

1. 1

   Depressurize the System

   Safely park the tractor, turn off the engine, and completely drain/depressurize the compressed air tank using the drain valve. Do not attempt to remove the sensor while the tank is under pressure.

2. 2

   Locate the Sensor

   Locate the B019 pressure sensor, which is threaded directly into the compressed air storage tank.

3. 3

   Disconnect Electronics

   Unplug the electrical harness connector from the sensor.

4. 4

   Remove the Sensor

   Using an appropriately sized wrench, carefully unscrew the faulty B019 sensor from the tank.

5. 5

   Install the New Sensor

   Thread the replacement sensor into the tank. Tighten it to the manufacturer's specified torque (avoid over-tightening, which can damage the threads).

6. 6

   Reconnect and Test

   Reconnect the electrical harness. Start the tractor and allow the air compressor to build up pressure. Verify that the dashboard indicator now displays the correct air pressure and that the fault code has cleared.