Fendt 04.1.86 – Transmission Control System (A050 or A002 ECU): Plausibility error in both pressure sensors

The signals from the two high-pressure sensors in the transmission's high-pressure circuit do not match, or they are being read incorrectly by the control unit.

• 922 Vario COM III
• 924 Vario COM III
• 927 Vario COM III
• 930 Vario COM III
• 933 Vario COM III
• 936 Vario COM III
• 207
• 208
• 209
• 210
• 211
• 309
• 310
• 311
• 312
• 313
• 409
• 410
• 411
• 412
• 415
• 711
• 712
• 714
• 716
• 815
• 817
• 818
• 820
• 824
• 916
• 920
• 924
• 926
• 930
• 936

1. 1

   Check the 8.5V or 12V power supply to the sensors at the A013 fuse board (fuses 3, 10, 15, or 31 depending on model).

2. 2

   Inspect wiring and connectors at separation points X157 (B008 sensor) and X177 (B039 sensor) for corrosion or damage.

3. 3

   Perform a high-pressure test using the Variotronic Ti terminal or a multimeter (approx. 0.8 VDC at 0 bar, 0.94 VDC at 30 bar).

4. 4

   Check transmission temperature via sensor B009 to ensure the transmission is not overheating and skewing pressure readings.

1. 1

   Access the Valve Block

   Locate the B008 and B039 high-pressure sensors on the right side of the transmission, directly on the hydraulic valve block.

2. 2

   Remove Obstructions

   Safely lift and support the tractor, then remove the right rear wheel and the protective metal side panels.

3. 3

   Disconnect Electrical Connections

   Carefully unplug the X157 and X177 connectors from the B008 and B039 sensors.

4. 4

   Remove the Sensors

   Unthread the faulty sensors from the hydraulic manifold. Have a catch pan ready for minor hydraulic fluid loss.

5. 5

   Install New Sensors

   Lubricate and install a new O-ring upon reinstallation. Thread the new sensors into the ports and tighten to the manufacturer's moderate torque specification (do not over-tighten).

6. 6

   Reassemble and Calibrate

   Reconnect the wiring harnesses. Reinstall the metal panels and the right rear wheel.

7. 7

   Clear Codes and Test

   Turn the ignition ON, clear the fault codes via the Variotronic Ti terminal, and run a transmission calibration (Note: The B008 sensor must be installed and functioning properly to successfully calibrate the transmission). Check for leaks at idle and high RPM.