i have a carrier air conditioner- set thermostat inside maintained desired temp. during the night but woke up to find outside fan was still running and would not turn off- noticed this several times lately when i would go outside after unit had turned off inside- frost on one of the pipes coming from fan area covering- i am about to leave for the summer-what is my problem- i pulled the power in my electric box and it stopped- but i will need the air on later!!! help!!!!

it sounds to me like your contactor might be getting stuck or might be stuck permenantly. this would keep your outdoor fan and compressor running all the time. this would also make your suction line start to freeze. not a costly repair but a needed one. you are wasting tons of money on your electric if it is running all the time.
call a local hvac company to come repair the part. they should have one on thier truck.