Automatic Climate Control
5 Year Member
Joined: Nov 2018
Posts: 6,724
Likes: 3,944
From: Calgary, Alberta
Thank you for the information!
I did notice one other thing today, and I don't know if it is related to the Climate Control AC. Normally my coolant temp digital readout will vary between 199 and 205, irregardless of ambient temp. Today, I noticed it going as high as 215, and then would drop back, which it has never done before.
I did notice one other thing today, and I don't know if it is related to the Climate Control AC. Normally my coolant temp digital readout will vary between 199 and 205, irregardless of ambient temp. Today, I noticed it going as high as 215, and then would drop back, which it has never done before.
Thread Starter
5 Year Member
Joined: Jul 2015
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From: Durham, NC
Junior Member
Joined: Sep 2016
Posts: 2
Likes: 2
From: Murrieta, CA
Just the info I was looking for.
From the WSM:
Ambient Air Temperature (AAT) Sensor
The Ambient Air Temperature (AAT) sensor is an input to the PCM. If the outside air temperature is below approximately 0°C (32°F), the PCM does not allow the A/C compressor clutch to engage. The PCM sends raw ambient air temperature data to the FCIM. The FCIM filters the raw data, sends it to the APIM and the touchscreen displays the outside temperature.
After replacing an Ambient Air Temperature (AAT) sensor, the sensor data must be reset by either driving the vehicle at speeds consistently about 20 MPH for at least 5 minutes to update the filtered data or perform the multiple button press reset procedure to update to the current raw value.
value...
Ambient Air Temperature (AAT) Sensor
The Ambient Air Temperature (AAT) sensor is an input to the PCM. If the outside air temperature is below approximately 0°C (32°F), the PCM does not allow the A/C compressor clutch to engage. The PCM sends raw ambient air temperature data to the FCIM. The FCIM filters the raw data, sends it to the APIM and the touchscreen displays the outside temperature.
After replacing an Ambient Air Temperature (AAT) sensor, the sensor data must be reset by either driving the vehicle at speeds consistently about 20 MPH for at least 5 minutes to update the filtered data or perform the multiple button press reset procedure to update to the current raw value.
value...
Replaced my radiator yesterday (2017 Platinum 4X4). Very tight fitment of the four main components (fan shroud, radiator, AC condenser, trans fluid cooler), meant the AC condenser got smacked around a bit. Had to make a couple short drives this afternoon, but I still hadn't reinstalled the grill, which means the ambient air temperature sensor was not connected. I started freaking out thinking I had damaged one of the AC lines or cracked something on the condenser and lost my refrigerant because the AC never kicked on. But the reason for that was actually due to the AAT being disconnected. Learned that here, from you. Thanks again, 52merc!
Incidentally, when disconnected (or electrically open) the AAT sensor throws the P0073 code and 50⁰ is persistent as the outside temp.