Help A/C shuts down restarting car required
 

When I go full throttle my a/c shuts down (blows warm) The only way to reset it is to park, shut off, and restart the car. Manually shutting off a/c and turning back on does not reset it when the car is running. I have to restart the engine to have a functioning a/c. Could it be a bad relay? If so where would I find it. Thanks