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So I don't know what the hell happened but my car thinks it's 0F outside! It's going to be in the 80s and 90s next couple of days please help me troubleshoot this!
 

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Lol I wish it was that cold in NJ, it's too damn hot! I remember one of first guys to pick up there RS (UK I believe) had it reading like -18 Celsius. I would bring it to the dealer have them look over it.


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Was hoping it would be something I could fix but it's too hot to deal with this BS. Drop off and loaner car for the rest of the week I'm guessing. Oy vey.
 

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Was hoping it would be something I could fix but it's too hot to deal with this BS. Drop off and loaner car for the rest of the week I'm guessing. Oy vey.
Check fuse F85 circled in blue located under the glove compartment.

 

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Maybe unhook the battery and reattach for a reset???
 

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Discussion Starter #7
I think something else might be the issue because the car has been off for 3 hours and the engine coolant temp is still sitting at half. Wtffffffffff I did nothing but my normal commute home today :(
 

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I think something else might be the issue because the car has been off for 3 hours and the engine coolant temp is still sitting at half. Wtffffffffff I did nothing but my normal commute home today :(
Coolant temp basically stays at half from 140 degrees onward. It's entirely plausible that it'd still be that warm after 3 hours in the summer.
 

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Thanks for the help @j0shm1lls
Sorry that wasn't the fix, only reason I recommend it was because when I was installing my dash cam that fuse wasn't seated properly and i noticed the zero temp thing also. It fixed itself shortly after reseating that fuse. Good luck!
 

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Sorry that wasn't the fix, only reason I recommend it was because when I was installing my dash cam that fuse wasn't seated properly and i noticed the zero temp thing also. It fixed itself shortly after reseating that fuse. Good luck!
Is the actual sensor harness anywhere around where you replaced your intake with the mountune intake? Maybe when you disconnected or reconnect a harness it fixed the problem then? Any chance you did that when you did the fuse as well? The sensors are usually somewhere up front but the connector in the bay behind radiator.
 

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I had this happen on mine about a week ago. Was fine on my drive to work. Go to lunch and it's reading 0. Since the AC system thought it was 0 deg outside and I had the AC set on 71 deg it was blowing serious HOT air inside (this on a 95 deg day!). Turned off climate control system. Got back from lunch. let it sit for a while and started it again, same thing, 0 deg. Later I drove home, with a stop at my dealer on the way, and about 5-6 miles up the road I notice the temp slowly rising until it got to 93, turn the air back on, everything's fine.

The dealer has seen this happen on other Fords and ordered a new ambient temp sensor, which on the RS is in the right outside mirror so...they had to order an entire mirror assembly. While the mirror was on order it didn't happen again. They replaced the mirror this last Saturday 7/16. Everything was good until lunchtime today when I notice it is reading 75 deg (it was 95 out again) and not moving. Fortunately the AC would still work. It behaved the same as the first time - I'm driving home and several miles up the road it finally starts reading the correct temp again.

Have to call the dealer tomorrow and see what they want to do next.
 

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Is the actual sensor harness anywhere around where you replaced your intake with the mountune intake? Maybe when you disconnected or reconnect a harness it fixed the problem then? Any chance you did that when you did the fuse as well? The sensors are usually somewhere up front but the connector in the bay behind radiator.
As @PiSigma said, the sensor is in the passenger side mirror, there's a little nub that hangs off the bottom of it. I didn't unplug/plug any harnesses at all until this past weekend when I installed my mountune quickshift (the intake air temperature sensor) but my outside air temperature sensor was already working by then. The only thing I can attribute it to is that fuse or a coincidence.
 
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Thanks for the help @j0shm1lls
@turb0charged try this - from the shop manual! :)

Ambient Air Temperature Sensor

The Ambient Air Temperature (AAT) sensor contains a thermistor. The sensor varies its resistance with the
temperature. As the temperature rises, the resistance falls. As the temperature falls, the resistance rises. The
Ambient Air Temperature (AAT) sensor is an input to the PCM through separate input and return circuits. If the
outside air temperature is below approximately 0°C (32°F), the PCM does not allow the A/C clutch to engage.

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.

  • On the HVAC panel controls, press the A/C and Recirc buttons simultaneously, then release both.
  • Within 2 seconds press the A/C button again.
EDIT: Further information below

Outside Air Temperature Display

The Ambient Air Temperature (AAT) sensor provides the Ambient Air Temperature (AAT) data used for the outside
air temperature display in the IPC. The ambient air temperature sensor is hardwired to the PCM through separate
input and return circuits. The PCM provides a reference voltage to the ambient air temperature sensor and
monitors the change in voltage resulting from changes in resistance as determined by outside air temperature.
The PCM filters the ambient air temperature input and sends the BCM the air ambient temperature filtered
message. The BCM sends the air ambient temperature filtered message to the IPC.

Due to the location of the Ambient Air Temperature (AAT) sensor in the RH exterior mirror area it is greatly
influenced by heat generated from inside the mirror. For this reason the outside air temperature value displayed in
the IPC does not update in the upward (hotter) direction under 33 km/h (20 mph). This update strategy is used
temperature rise or by heat generated from inside the mirror.

The outside air temperature display in the IPC updates in the upward (hotter) direction under either of the following
situations:

  • if the vehicle is driven over 33 km/h (20 mph) continuously without the vehicle speed dropping below 33 km/h (20 mph) for approximately 90 seconds.
  • if the vehicle is allowed to sit with the engine off for approximately 6 hours (the outside air temperature display in the IPC immediately updates to reflect the current ambient conditions since the engine has cooled sufficiently and no longer has an effect on the outside air temperature sensor reading).
NOTE: If the vehicle speed drops below 33 km/h (20 mph) before the outside air temperature display in the IPC
begins to update the PCM logic resets and the time starts over.

Because this filtering strategy exists, it may be necessary to drive the vehicle continuously above 33 km/h (20
mph) for approximately 90 seconds when observing the outside air temperature display operation. After the
vehicle has been driven above 33 km/h (20 mph) for 90 seconds, the outside air temperature display in the IPC
should start to filter upward toward the actual outside air temperature. Depending on the difference between what
the outside air temperature is displaying in the IPC and the actual outside temperature it can take several minutes
for the outside air temperature display in the IPC to reach the outside temp.

The outside air temperature display in the IPC does not filter in the downward (colder) direction and always
displays the coldest temperature detected by the sensor even when the vehicle is stationary. When the outside
Ambient Air Temperature (AAT) is lower than the temperature displayed in the IPC, the IPC immediately updates
the displayed temperature downward to reflect the colder ambient air temperature, even at idle.
 

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Discussion Starter #17
Start the car this morning and it's working fine... Serious side eye is being given to the car and Ford. Will hit the dealership just so this is on file.
 

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Start the car this morning and it's working fine... Serious side eye is being given to the car and Ford. Will hit the dealership just so this is on file.
May have better luck getting it on file with Ford Service via Facebook. I don't think my dealer filed my report of the b-pillar rattle and that I planned to wait to bring it in until I see a TSB and hear from others that it fixed their problem.
 

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Sounds like the ambient temp sensor might be unpluged
 

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I had the same issue where it was stuck at 75, theres also been a few reports over on the British site (as someone mentioned over there.)

I will stay tuned to this thread.
 
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