Speed passion esc problem.....Help,
 

This is my first first post so please go easy! I have a speed passion inspire Cirtix 2 esc which has stopped working after a minor crash. When switched on with full battery, my buggy's steering servo works fine, but motor remains off. the yellow led on the esc is lit continuously, and a high pitched sound seems to be coming from the speed passion motor !! (if that's possible!) but the motor won't turn at all. This high pitched sound stops when I apply any throttle (forward or reverse) I'm very new to this, so any help would be appreciated!!