The location of the sensors 

Welcome to the forum.

 

Some more context in a post like this would be very helpful?

 

Do you have twin or tri climate control? What temp are the rear vents running at?

 

Have you scanned for fault codes?

What sensors are you looking for? If it’s the temperature sensors they are scattered everywhere and there are a lot of them.

some in vents, others in the heater box itself, humidity sensors, air quality sensors, flap position sensors