Had my front window clear tinted, now my Outside Temp Sensor is reading -34f...

I just got back from picking up my 22 Pro from having Llumar Air 80 put on the front window and noticed my a/c wasn't working (it was warm here today). Happened to notice the outside air temp on the dash was -15f. Pulled over and went out there and dis/reconnected it and started it back up...-34f.

By the time I got home (35min drive) it had risen to -24f.

When I got home I pulled the plastic housing that covers the front facing camera/sensors and there is tint under the lip of the shroud, so I know they've been in there.

My question is, is there anything else in that front facing housing that would have any effect on any sort of temperature sensing? All of this was working fine before I dropped it off...it could just be a matter of a spontaneously bad ambient temp sensor under the hood...it's a $43 part so I might just chuck it at it and see if it works.

Anyone else have anything like this ever happen? I was looking through the forums and there are a lot of 'erratic' temp reading posts, but nothing sub-zero in 70f weather and it not warming up after a long drive.

 

what "front facing housing" are you messing with? A pic would help the pros here.
Not sure where the temperature sensor actually is, but someone here probably will. Used to be, they were often in the air intake system, taking a reading off of the same sensor the ECU is using for mapping,,, but I am so far behind the times, I doubt that's accurate anymore.
Did you call the shop and explain? They may have done this before and have a quick fix, or need to know incase repairs become more involved.

GL and welcome

 

Pretty sure the temp sensor is under the hood so dunno how tint would have any impact on that

can try disconnecting your battery for a bit and see if that fixes it, but beyond that I’d think the sensor needs replaced.

 

In general - if you just got tinted, give the truck a few days to chill out. Sometimes the signals get all wonky (especially after tinting the full shield) until all the condensation clears up.

They also should not have tinted the full upper section behind the plastics. There's no point and it can cause issues with the sensor there.

 

Yah, sensor is under the hood on the support bracket where the hood latch is. Reseated the connection roadside and it went from -15f to -34f.

I considered pulling the negative terminal for a while but I'll check it in the morning to see if it's still a problem.

One thing that I did consider was water from the squeegee-ing process when putting the front tint on dripping behind the dash on something causing a short/bad reading.

 

They didn't tint the full upper section, but the tint extends like 1mm under the shroud, so I know they've been in there.

I'll give it a few days and see if anything changes...bad time for the a/c to be unusable, tho.

 

its behind the grill

 

Can anyone post up a wiring diagram?

Does Toyota use two different temp sensors? I'm thinking there is more than one.

1) Intake Air Temp ==> This sensor is almost universally located near the front grill where intake air enters the air filter housing. This sensor controls the PCM / ECM for fuel mgmt and more. This, I believe, is an independent sensor.

2) Outside Air Temp (or Exterior Temp) ==> Like what shows on your dash. I'm wondering or thinking this sensor may be located on the front windshield, near the rear view mirror, and now fouled by this new coating. Or the sensor was mucked up during the coating install?

The outside air temp may not be the same as the intake air temp. Think about driving on a cold, slushy, roads but on a bright sunny day.

IAT near the grille might be 10-20 degrees or more colder than the OAT windshield temp sensor.

-----------------------

Plug in a scan tool. If you don't have one, proceed to your nearest local brick-n-mortar auto parts store and ask them to scan it for you.

If your IAT is reading normally, say 78F but your dash display is still reading -34F then you have your answer

 

It is a part of MAF sensor

 

^^ OK, this makes sense^^ No better place than to measure IAT Intake Air Temp.

Where is the OAT Outside Air Temp sensor located?????????

-------------
Apologies for the questioning. I am WAY more familiar with Ford Mustangs and have access to wiring diagrams since 2005.

If I had the same for these trucks, I could (would) be more definitive

 

Wow. I would not have guessed it there. Thanks for sharing.

 

Minor update(s):

Just went out and checked and now it's reading 34f...it's 45f here currently. So, an improvement.

Also found this thread for anyone that happens upon this one in the future:

https://www.tacomaworld.com/threads/outside-temp-gauge-ac-not-working.586102/page-4

Several reports of the same thing after having their windows tinted with no real answers, although I'm beginning to suspect squeegee water.

 

Check codes. If there are electrical issues, you should see B codes stored.