HVAC box what part is this?

[Bobaganousch]

Hey everyone!
I'm in a potential pickle and I am not sure that this information is widely known..
I am currently attempting to reassemble my HVAC unit from under the dash of my micra. Further posting coming eventually... And I have soaked the sensor that is located on the rear of the unit (Careless parts dishwashing that I will blame on not wanting to get caught by my wife... Which luckily she ended up being ok with!) I am not sure if I have killed it or not as I do not know what it does or how to test it..

It is located on the front side of the HVAC Box towards the bottom and has a 4 pin connector that attaches to it. It is a small circuit board inside but doesn't seem to be a sensor.. and trying to find something based of the numbers the part provides has returned negligible results for me.. I attached some pictures of what the part looks like. and a diagram of the HVAC unit. On the diagram the blue arrow points roughly to where the little box is located. It is on that front side and kind of to the right of the blower motor resistor.

Any thoughts would be appreciated.

As for now I am going to start reassembly, leaving this part to the side and see where that gets me.

Cheers!