Fendt 04.1.89 – Transmission Control System / ECU: B009 - Discharge temperature sensor (Plausibility error, transmission temperature)

The transmission control system has detected an implausible signal from the B009 temperature sensor, which monitors the discharge oil temperature of the transmission's high-pressure circuit. This means the sensor's reading is erratic, out of the expected range, or there is a fault in the sensor/wiring.

• 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 series
• Fendt 400 Vario series (Farmer 400)
• Fendt 700 Vario series (Favorit 700)
• Fendt 800 Vario series
• Fendt 900 Vario series (Favorit 900, COM III, and S4 generations)

1. 1

   Check Terminal Readings: Use the tractor's Variotronic Ti terminal and navigate to the Diagnose 2 menu. Look for the reading from the 'Temperature sensor discharge B009' to see if it fluctuates wildly or shows an extreme temperature when cold.

2. 2

   Locate the Sensor: The B009 sensor is typically located on the right side of the transmission, mounted on the valve block (infeed and discharge). Remove the right rear wheel and a protective metal panel to access it.

3. 3

   Inspect Wiring & Connector: Check the separation point connector (designated as X158) on the B009 sensor for broken wires, corrosion, or moisture.

4. 4

   Test the Sensor: Use a multimeter to test the resistance of the sensor to see if it has an internal short or open circuit.

1. 1

   Park tractor

   Park the tractor on a level surface, turn off the engine, and engage the parking brake.

2. 2

   Remove wheel and panel

   Remove the right rear wheel and the protective metal panel to gain access to the right side of the transmission valve block.

3. 3

   Disconnect connector

   Locate the B009 discharge temperature sensor and disconnect the X158 electrical connector.

4. 4

   Inspect and clean connector

   Inspect and clean the connector contacts with electrical contact cleaner. If the wiring harness is damaged, repair the affected section.

5. 5

   Prepare for oil catch

   If the wiring is intact but the sensor is faulty, place a catch pan underneath the valve block to catch any residual transmission oil.

6. 6

   Remove sensor

   Unscrew and remove the old B009 temperature sensor.

7. 7

   Install new sensor

   Install the new B009 temperature sensor and tighten it to the manufacturer's specified torque.

8. 8

   Reconnect connector

   Reconnect the X158 electrical connector.

9. 9

   Reinstall panel and wheel

   Reinstall the protective metal panel and the right rear wheel.

10. 10

    Clear fault codes

    Turn on the tractor and use the Variotronic terminal or SERDIA diagnostic software to clear the stored fault codes. Verify that the temperature reading is now plausible.