Where is the ambient temperature sensor located?

[solidONE]

The ambient temp sensor seems to be very inconsistent, if not inaccurate all together. Where is the sensor located? Maybe it needs some heat shielding or relocated where it can pick up accurate temps.

[CSG Mike]

Passenger side, in front of the AC condenser. It has its own bracket, and the harness is tied to the front horn.

It'll read accurate in free-flowing air; it'll read high when you have a hot parked car.

[FRSBRZGT86FAN]

Originally Posted by solidONE

The ambient temp sensor seems to be very inconsistent, if not inaccurate all together. Where is the sensor located? Maybe it needs some heat shielding or relocated where it can pick up accurate temps.

A lot of vehicles, not just the FR-S, have this problem. First off air needs to be flowing for a few minutes through for it to get an accurate temperature reading (it's connected to a clip on the condenser) and looks like this and has a part number of SU003A0022:


Also it's inconsistent but a lot of variables play into it like:
What temperatures are you comparing it too? A weather app on your phone or an actual thermometer off the ground? In either case those temps aren't measured in the exact location and also aren't the same height over asphalt in an area with little airflow like inside a car. Also color of the car has a lot to do with the temperature readings as well if the car has been sitting.

If you're really annoyed by the temps in toyota techstream there's an ambient temp sensor offset you can set as well. Honestly I don't find it a big deal though it needs to be driven around a bit to get a correct temp

[solidONE]

I went ahead and measured the temperature of the components around and touching the temp sensor after having warmed up the car and driven for about 10 minutes. Ambient temperatures were at around 90-92. The mounting bracket was 110 degrees and the AC condenser was about 105 degrees few seconds after having stopped the car. Not a huge difference, but I'd think if it were mounted on the plastic shroud just a few inches ahead of where it's siting now it would read more accurately. Or at the very at least not take so long to get the air temps coming through the grill opening.

I've been keeping a close eye on the ambient and intake temps after having changed up some hardware on the car, in case you guys are wondering why im being so anal about the accuracy. I suppose ideally the ambient temp sensor would be mounted right next to the intake snorkel opening.

[solidONE]

The ambient temp sensor is definitely affected by heat-soak. It will read a few degrees hotter after you've brought engine temps up and past normal operating temps regardless how fast you are moving.

I'm thinking about relocating it to where the horn is mounted ahead of where it's at now using a aluminum bracket instead of the steel one it currently is attached to.

[Hags86]

Does anyone have the calibration data for this sensor? It is originally wired to the dash but I’ve got an aftermarket dash and have wired this to the Motec ECU and would like to still read outside temp data.

[solidONE]

Originally Posted by Hags86

Does anyone have the calibration data for this sensor? It is originally wired to the dash but I’ve got an aftermarket dash and have wired this to the Motec ECU and would like to still read outside temp data.

In romraider

[Hags86]

Thanks. I assume these voltages are with 5V source and a 1k Ohm pullup resistor?

[solidONE]

Originally Posted by Hags86

Thanks. I assume these voltages are with 5V source and a 1k Ohm pullup resistor?

sounds about right, but

[dynarun55]

Originally Posted by solidONE

The ambient temp sensor is definitely affected by heat-soak. It will read a few degrees hotter after you've brought engine temps up and past normal operating temps regardless how fast you are moving.

I'm thinking about relocating it to where the horn is mounted ahead of where it's at now using a aluminum bracket instead of the steel one it currently is attached to.

Not sure if you guys are active but has this ever caused no start by any chance ? I park my car outside for 8 hours in an uncovered parking lot under the 110 F Texas Sun and sometimes when I try to start, all the electricals turn on but no crank. I can only reproduce this error state in extreme heat. Nobody has been able to diagnose this so far. I had all the electrical system checked out and didn't find any issues.

Sent from my Pixel 6 Pro using Tapatalk

[Trap63]

Originally Posted by dynarun55

Not sure if you guys are active but has this ever caused no start by any chance ? I park my car outside for 8 hours in an uncovered parking lot under the 110 F Texas Sun and sometimes when I try to start, all the electricals turn on but no crank. I can only reproduce this error state in extreme heat. Nobody has been able to diagnose this so far. I had all the electrical system checked out and didn't find any issues.

Sent from my Pixel 6 Pro using Tapatalk

My relocation of temp sensor