Hello , After landing in a tree, I saw to display the message "Motor obstructed". When I try to restart my phantom ( without propellers ), I see that one of the engines does not start; but I can rotate freely by hand. Do I have a way of knowing whether the motor or ESC is broken? Is it possible to change only one ESC on the P3A, if it is burned? I believe ESC seat on the mother board ! Thank for your help.