Two problems...anyone please help.

1. Aircon not working, the green light on the aircon button flashes...whats the problem? how to fix it?

2. My horn isnt working, just all of a sudden, it works on and off, mostly off?

1) i am guessing compressor problems on your air-con. have you changed your drive belts lately?

2) horns prob due to a blown fuse or some electrical fault somewhere. doubt it's the horn cos if it is it won't work at all. have an auto-electrician check it out.

You might find that you are out of air-con gas.There is a switch near the reciever/dryer that when gas is running low cuts out to save the air con from damage.Was the air con running ok ie., cold or just enough

The aircon was running cold and normal, i was driving the car around a corner one morning, i hurd a big CRACK from the engine, car lost power. i pulled over, turned the car off. turned the car back on, everything back to normal, no loss in power...one thing different...the aircon wasnt working.

Might be a belt??

3rd generation Magna
Howdy, the flashing green light indicates that the compressor and eng speed have a major difference resulting in the air con being switched off by the computer (clever little bugger that computer), this prevents belts being destroyed.
Hope I'm wrong for the next bit, but if it has worked as per advertised then your comp could have siezed or fan belt broke.
To check it you will have to remove fan belt, power the mag clutch with a bypass lead and try to turn the compressor by hand.

In other words, get it to a mechanic or mitsu so further damage does not occur.