Hello

My Engine Management Light came on approx. the 15th January.
I took it to a friend for a diagnostic and the fault was the Intake Air Temperature Sensor 1 Circuit. My friend reset this and did pre warn me the Engine Management Light would likely come back on in which it did back end of last week. I have warranty on the car so thought I would book it in with my dealer and is due to go in this Friday. However to my surprise, tonight, the Engine Management Light has gone off

Apologies for the novice question but should I still take the car in? Should I explain to the dealer I have had a diagnostic?

Thanks in advance for any help