So, I experience a flyaway a few weeks ago and sent my drone to DJI as it was still under warranty.


They finally got back to me and told me that 'An MC was replaced and the drone was fully updated and calibrated'


I am not very technical.  What is an MC?  I am assuming it has to do with one of the motors??  More importantly, could this have caused a flyaway?  


Looking forward to your replies.


Thanks

If it flew away how did you send it back for repair ?
MC for the Phantom normally means the NAZA unit, although that can also be called the FC (flight controller).

They are most likely referring to the master controller. Before you fly again I hope they told you to re- calibrate the IMU and the compass. Both can get disoriented during shipping and need to be re calibrated for your location and it sets the sensors for the. Accelerometer, gyroscope and helps stability with roll, pitch and yaw. And allows the electronics to calculate the required power to each of the motors needed speeds.
If they didn't then you still need to perform these functions to help prevent another fly a way.

I managed to find my drone after hours of searching in the general direction it flew away in..  I was lucky.    Does flying in atti mode reduce the risk of flyaways?

They told me MC refers to the main controller.  

Still waiting to receive it.  Maybe today or tomorrow.