When mine is updated, (much more than a few miles), it is as accurate as expected. I must say with other GMC, Honda's, and Toyos I have and still own, this truck is absolute garbage with response time on the Temp sensor. And the DTE, and MPG are dismal as well. Don't get me wrong, I like my truck, just saying other manufacturers are superior with the extras, bells and whistles, hands down and I'd hate for anyone hoping to by a new truck as I did to have a false illusion that they aren't. I sure hope this new truck lasts 200k like by 2005 GMC YukonXL did with little maintenance per the manual.

 

Yeah, that information the AAT is interesting and good to know (thank you), but the sticking at one temperature is what I'm experiencing. I have noticed when it seems to be operating correctly as I pull out of the warm garage and the temperature methodically and gradually drops as I drive. However it doesn't seem to be working when the temp just stays steady at the same temp it was when I last turned off the truck.

Yesterday morning I made a trip from my garage where the temp dropped from the 50s to 18 before I returned to my garage for a few hours. I then left my garage to make a short run to a drive-thru for lunch and the temp read 18 the entire time. I didn't even change from having sat in the garage or with the outside temp having warmed into the upper 20s.

What did they do to fix yours since you mentioned you have one working properly now? I'm coming up on my 3 year warranty expiration and want to make sure that it gets fixed if there is something broken. I wonder how the shop will be able to verify my issue?

 

Yeah, I'd say 6 degrees off is a pretty fair estimate of how far off it quite often is. So if both are wrong and nothing is right, then everything is fine.

 

Agree. I have had vehicles with thermometers for decades and I've never seen one anywhere near as bad as this one. Ford has explanations I'm sure but really it's incompetence, as it is not a complex nor expensive thing to design.

Freezing door latches, clunking transmission, warped dashboard, and nearly worthless thermometer. It can be downright embarrassing to give people rides in this truck. In many ways it's like a time machine to the early '80s. It doesn't give me confidence in its long term reliability, that's for sure.

 

I do appreciate the information... Since you seem to know a bit about how the outside temp reading impacts how the truck behaves, I thought you may be able to provide some insight to this scenario I've experienced...

I've had IWE issues in the past and eventually learned that they engage for 3km to warm up the transfer case when the outside temp is below 32F. I can tell when they're engaged (more road noise, slightly different drive feel) and can tell when they disengage exactly 3km or 1.8 miles down the road. In the morning I will leave my warm garage and they are not engaged since the temp reading is above 32F in my garage. As I drive my daughter to daycare, I notice as the temp reading gradually drops over the course of the 15 minute drive. After I get back in the truck to drive home, the temp reading has reached below 32F (since it was parked outside) so I can tell the IWEs are engaged for 1.8 miles. In the case of my lunch trip described earlier, I then parked in the warm garage at home and returned to my truck a few hours later for my lunch run. The temp still read 18F in my display, but I could tell that the IWEs were not engaged. So, not only did I know the outside temp was warmer than 18F in my garage, but the truck must've also "known" it was not below 32F otherwise it would've engaged the IWEs, right? For some reason it just continued to show the old 18F reading throughout my drive to grab lunch. It's another clue that leads me to believe the temp is not displaying correctly in certain scenarios.

Based on this, any further thoughts on why this could be happening? Thanks again!

 

I was looking into this also and have learned that the temp sensor is now located in the passenger side mirror (vs the grill areas like most vehicles). I'm curious if delays in reading accurate temps might also be related to allowing that air space to stabilize a bit; especially if that mirror was exposed to the sun, etc.... Possibly a comparison against Intake Air Temp?

 

Mine is on the bottom of the passenger mirror, and is usually within a couple degrees of other local sources (the thermometer on my porch, nearby weather stations, etc.). My guess is that it was moved away from the grill area for better airflow and reduced error from under-hood heat sources. I wonder if it can be replaced without replacing the whole mirror.

 

The PCM gets the raw information from the sensor, so as soon as you start your truck, it sees the new temperature. The IWEs don't engage since it knows the temperature is above 32°F. The PCM also checks engine temperature, and if this is above the AAT reading, it won't engage the IWEs even though ambient temperature is below 32°F (this indicates that you've recently driven the truck). The APIM gets a filtered signal from the PCM, so the temperature takes some time to change. On your drive to lunch, do you exceed 20 mph for at least 5 continuous minutes? Don't ask me why the display temperature gets filtered, I have no idea and I don't work for Ford.

 

Outside temp is frozen on -39 degrees any idea on how to correct it ?

 

Your AAT sensor has probably failed or there is a wiring issue between the AAT and the PCM. This can be confirmed by checking for DTCs with a scan tool such as FORScan.

The sensor is mounted in behind the front grille or in the passenger side mirror, depending on the MY of your F150.