Cabin Temparature Sensor Issue/location

[dali22]

Hello Everyone
I have 2013 titanuim Fiesta with Auto A/C, the issue is that it seems that the Cabin temparature sensor is faulty it reads -31c on forscan and sometimes it works just fine.
if I set the AC to LO there's no issue at all, other than LO the Vents will Blows hot air at (16c, 17c, 18c .....)
I've read on the forum that the location of the sensor is behind that little grille next to driver, theres nothing I've followed this video

but couldn't locate it
is there Any other location that I should look into
can anyone help

thank you

 

[Handy Andy]

Welcome to the forum!

Hopefully this temperature sensor is by the Cabin Air Filter - just towards the passenger side.

In the US, it's located on the Right side, by the Cabin Air Filter - so that means you'll have to remove trim, in the US-kind or wiring, it's a bright blue body and you turn it a partial turn and pull it out - then you can disconnect it from the harness/connector and inspect it.

It's in the airflow on the Climate control housing - so it's "body" is to the outside, but the sensor tip is in the inside hollow of that blower unit to sense the temperature.

 

[dali22]

Thank you for your answer Andy
I believe that that Sensor is the Evaporator Discharge sensor
Following Your Advice I removed that one The Compressor Didn't Engage and Had a New DTC mentioning that there's an is issue with the evaporator and still Getting the B1A61 DTC it turns out that there's another temperature Sensor than the Evaporator which is faulty I installed it again, the AC worked as it was before still getting Hot air at 16c

 

[Handy Andy]

Yep, that was the one I was thinking of.

Might want to get another one, see if this one shorted or is giving erroneous readings.

The code declares an issue - like a short - in the harness to this sensor, but if the thermistor itself is bad, then the game is afoot in the sensor itself.

Now, next question, do you have the "Manual Climate control" or the Automatic one where it reads the cabin temperature as a numeric on the main center knob of the climate control?

Reason? Manual Climate control only uses one sensor, while the Automatic one, uses two.



One in the footwell, that blue one you found, and another that is in the dash/console- thru the Automatic Climate Control unit.

This is the "Manual" and also shows "Rear Defrost / Heated Windshield" feeder (50A) off of that big Red Terminal Box on the battery's Positive post.

Manual is this...

Automatic uses two air sensors in the output airflow from the unit - and works with the "Sunload sensor" or the lighting system - to offset the hotter dash when the sun beats down on the small dash.
And on top of the fact there is a THIRD one in the Cabin.
​

That one is by the Air Recirculation door - it "tests" the air and runs the Recirculation to outside air, as it sees fit - per your temperature setting.

To help with this - look at the Color Code of the sensor you found, it should match one of the above.

With all these sensors, the Automatic one, is the most complex and you'll need the color code for each sensor to help identify it in the harness and by it's connection location.

 

[Handy Andy]

As I thought about this more...

The past few months it's been very Hot and Humid, so the AC for anyone in stop-start traffic and congested intersections, they need cooling but the evaporator that cools down the air, also generates a lot of dew and moisture from the lowered dewpoint - so the sensors in the airflow can get wet from the dewed air mixing with the hotter cabin air that still has that humidity in with it.

So - that means these sensors can get "wetted" by that water and can affect their operation - especially if the drain hose used to get rid of the moisture is not perfectly cleared or is hindered from draining - that leftover water can get into that sensor and can skew your reading and even setting a fault code.

The job is not yet done for it may require that you take out or at least pull out the climate controls so you can check the connector and make sure it's seated and properly locked in position so it can retrieve the sensor information it needs to operate without setting a fault code.

 

[dali22]

Thank you Andy for this helpful information,
I have the Automatic Climate Control, I think the one in the picture attached is the faulty one because searching for DTC B1A61 on google lead to that sensor but I couldn't find its location on the car, I might need to remove the AC control panel and look behind it as it may be located there