Fendt 10.1.39 – A038 - ECU, central electrical system / A053 - ECU, air conditioning control: B076 - Sensor, external temperature - Function non-operable

The system has detected that the sensor values have exceeded the specified limits, or the specified values are not being reached. This typically indicates a broken wire, a short circuit, or a completely failed sensor. The air conditioning system will default to running in emergency mode.

• 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 (COM III)
• Fendt 400 Vario (COM III) (e.g., 409, 410, 411, 412)
• Fendt 700 Vario (COM III & SCR) (e.g., 711, 712, 714, 716)
• Fendt 800 Vario (COM III & S4) (e.g., 815, 817, 818, 822, 824, 826, 828)
• Fendt 900 Vario (COM III, SCR, & S4) (e.g., 916, 922, 924, 927, 930, 933, 936, 939)

1. 1

   Locate the B076 external temperature sensor on the front of the air conditioning condenser (or reverse side of the panel).

2. 2

   Inspect the wiring harness and the main separation point connector (X1538) for corrosion, moisture, or broken wires.

3. 3

   Test sensor resistance (Ohms) and signal voltage (VDC) at connector X1406/X1538 using a multimeter. Compare to ambient temperature specs (e.g., 20°C should read 13 kOhms / 3.1 VDC). An open circuit or dead short indicates internal sensor failure.

1. 1

   Turn off the tractor and remove the key to ensure the central electrical system is powered down.

2. 2

   Open the front bonnet to access the cooling package.

3. 3

   Locate the B076 external temperature sensor mounted on the front of the A/C condenser.

4. 4

   Disconnect the sensor at the X1538 separation point.

5. 5

   Unclip or unbolt the faulty sensor from its mounting bracket.

6. 6

   Install the new sensor and secure it to the condenser bracket.

7. 7

   Reconnect the X1538 wiring harness connector, ensuring it clicks into place and is free of debris.

8. 8

   Turn the ignition on and use the Vario terminal to clear the stored 10.1.39 fault code.

9. 9

   Test the air conditioning system to verify it has exited emergency mode and is blowing cold air based on the set cabin temperature.