Massey Ferguson 10.02.07 – AIRCON: Air Conditioning Outside Temperature Sensor Open Circuit (AIRCON)

The climate control system has detected infinite resistance (an open circuit) on the circuit dedicated to the outside (ambient) air temperature sensor. This is typically caused by a disconnected sensor plug, a broken/cut wire in the harness, or an internal failure of the sensor itself.

• 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
• 4700 Series
• 4707
• 4708
• 4709
• 4710
• 5600 Series
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 5700SL Series
• 7600 Series
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7700 Series
• 8600 Series

1. 1

   Locate the outside temperature sensor (usually mounted near the front grille, condenser, or cab fresh air intake) and check if it is physically unplugged or if the wiring has been snagged/torn by debris.

2. 2

   Disconnect the sensor and inspect the pins for corrosion, water ingress, or pushed-back terminals.

3. 3

   Using a multimeter, check for a 5V reference signal and a good ground at the harness connector (key ON). If voltage is missing, trace the wiring back to the AIRCON module to find the break.

4. 4

   Measure the resistance across the two pins of the sensor itself. If the multimeter reads 'OL' (Open Loop) or infinite resistance, the sensor has failed internally and must be replaced.

1. 1

   Power Down

   Turn off the tractor ignition and remove the key.

2. 2

   Locate and Access

   Gain access to the ambient temperature sensor. You may need to open the hood or remove a plastic cowl piece depending on the specific tractor model.

3. 3

   Removal

   Depress the locking tab on the electrical connector and pull it free from the sensor. Unclip or unbolt the sensor from its mounting bracket.

4. 4

   Installation

   Snap the new OEM or equivalent aftermarket sensor into the mounting bracket.

5. 5

   Reconnect

   Plug the electrical connector back in, ensuring it clicks securely into place to maintain the weather-tight seal.

6. 6

   Clear Codes

   Turn the ignition ON. The AIRCON module may self-clear the active code once it detects the proper resistance from the new sensor. If it remains stored as a historic code, use a diagnostic tool to clear the module's memory.

7. 7

   Test

   Turn on the A/C system and verify that the automatic climate control regulates the cab temperature properly.