My car AC only blows hot air

Don't panic — this is usually a fixable problem. First, check the simplest thing: is your AC compressor engaging? When you turn on AC, you should hear a click from the engine and feel the RPMs drop slightly. If you don't hear that click, the compressor clutch isn't engaging, which could be a fuse, relay, or low refrigerant. Second, low refrigerant is the #1 cause of hot air from AC. When refrigerant gets low, the system has a safety switch that shuts off the compressor to prevent damage. You'll need to get it recharged — this costs $150-300 at a shop. But here's the thing: if it's low, you have a leak. Just recharging without fixing the leak means it'll be empty again in weeks. Ask the shop to do a leak test. Third, check your cabin air filter — a clogged one restricts airflow and makes AC feel weak. It's a $15 DIY fix. Start with the filter, then get the system checked.