Massey Ferguson 10.X.10 – AIRCON: Air Conditioning Evaporator Temperature Sensor Short Circuit

The control module detects that the electrical signal from the evaporator temperature sensor is short-circuited (resistance is too low or the voltage signal is out of bounds). As a safety measure to prevent the evaporator core from freezing over, the system will automatically disable the A/C compressor.

• 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
• 5400
• 5600
• 5700
• 5608-5613
• 5710SL-5713SL
• 7600
• 7614-7626
• 7700
• 7714-7726S
• 8600
• 8670
• 8690

1. 1

   Verify that fault code 10.X.10 (or 10.00.10) is currently active.

2. 2

   Locate the evaporator temperature sensor (X443) on the HVAC evaporator housing in the cab roof. Disconnect it and visually inspect the wiring harness and connector for chafing, melting, or moisture that could bridge the pins.

3. 3

   Perform a sensor resistance test using a multimeter across the sensor's terminals. A reading near zero ohms indicates an internal short in the sensor.

4. 4

   If the sensor tests fine, perform a harness continuity test from the sensor back to the AIRCON module (roof harness X455). Check for a short to ground or a short between the two signal wires.

1. 1

   Turn off the tractor and disconnect the battery ground cable for safety.

2. 2

   Access the HVAC unit.

   Remove the outer cab roof panel or drop the interior headliner to access the blower and evaporator assembly.

3. 3

   Locate the evaporator temperature sensor (X443).

   It features a probe that is inserted directly into the fins of the evaporator core.

4. 4

   Unplug the electrical connector from the sensor.

5. 5

   Carefully pull the old sensor probe straight out of the evaporator core fins.

6. 6

   Insert the new sensor probe into the exact same location in the evaporator fins.

   Ensure accurate temperature readings and be careful not to bend or damage the delicate aluminum fins.

7. 7

   Reconnect the electrical connector.

8. 8

   Reassemble the cab roof or headliner panels.

9. 9

   Reconnect the battery, start the tractor, and clear the fault codes.

   Use the tractor's diagnostic menu or a diagnostic tool.

10. 10

    Turn on the A/C and verify operation.

    Verify that the compressor engages and the system blows cold air without logging the 10.X.10 code.