Massey Ferguson 10.02.01 – AIRCON: Air Conditioning Vent Temperature Sensor Open Circuit

The control module is not receiving a valid signal from the vent temperature sensor, typically because the electrical circuit is broken (open), a connector is unplugged, a wire is severed, or the sensor itself has failed internally.

• 7724S
• 5712SL
• 7722
• 7722S
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626

1. 1

   Locate the AC vent temperature sensor (typically mounted in the HVAC evaporator housing or directly behind the cab air vents) and inspect the wiring harness for chewed, chafed, or broken wires.

2. 2

   Unplug the sensor and inspect the connector pins for corrosion, moisture, or pushed-out pins. Reconnect it to ensure it wasn't simply a loose connection.

3. 3

   Use a multimeter to measure the resistance across the two pins of the temperature sensor. If the meter reads OL (Open Loop) or infinite resistance, the sensor has failed internally.

4. 4

   If the sensor tests good, check the continuity of the wiring harness between the sensor connector and the AIRCON module to rule out a broken wire in the cab harness.

1. 1

   Power Down

   Turn off the tractor ignition and disconnect the negative battery terminal to prevent electrical shorts.

2. 2

   Access the Sensor

   Remove the necessary cab interior trim panels or HVAC access covers to reach the AC vent temperature sensor.

3. 3

   Disconnect

   Unplug the electrical connector from the sensor.

4. 4

   Remove

   Carefully pull or twist the faulty sensor out of the evaporator housing/vent duct.

5. 5

   Install

   Insert the new temperature sensor into the housing, ensuring it is seated securely so air does not bypass it.

6. 6

   Reconnect

   Plug the electrical connector back into the sensor until it clicks.

7. 7

   Reassemble

   Reinstall all cab trim panels and covers.

8. 8

   Test

   Reconnect the battery, turn on the tractor, and clear the fault codes using a diagnostic tool. Run the AC system to verify that the vent temperature regulates properly and the code does not return.