170 bhp vrs tdi inlet sensor

Hi All, 

Little bit strange as I bought a high mileage vrs tdi. It is returning stunning mpg however I bought with the eml on  showing P2015 fault. The other day I'm sure coincidence but had to inflate a tyre and then reset the warning. So turned ignition to first switch reset tyre warning. Turned again and fired up. Interestingly the ping nor the light of the eml flashed up. Continued a 30 mile journey and other short trips not flashed up yet. I'm sure it hasn't gone away but I wondered what and where is the sensor that generates the P2015 'irregular' or word similar signal to illuminate the eml light. Its also reported flaps perm open flaps perm closed. I'm now really thinking it's the sensor. Thanks for your help.