h, I wants to know that my cars heating works but airconditiond doesn't works so what should I do to solve this,

Is it not blowing cold or just not turning on period?

If it's just not blowing cold, it's very possible that one of the component parts is leaking... the vehicle is already 15 years old. You'll have to take it to a mechanic who can perform a leak and vacuum test to determine where/if there's a problem.