Skip the auto shop - Our mechanics make house calls

Q: AC not working.

asked by on

The AC is not working. The fan does not blow cold air.

An A/C system can be divided into 3 different sub systems. These sub systems work for the most part independent from each other. The heater part of it works off of water from your engine. The refrigerant part is what makes the air cold, it is a sealed system that works similar to you home refrigerator. The last sub system is the duct and fan. This is what directs the air to the vent/floor/defroster, and actually blows the air. If the refrigerant system is low, a pressure sensor will detect this and not allow the system to come on. A technician will have the proper equipment to recharge your system and find the leak. Usually electronic leak detection equipment or ultraviolet dyes are used for this. Another common issue is actuator failure. Actuators are part of the duct system. They direct air from to the proper areas for cooling or heating. If the door that directs the hot/cold air is stuck half way or on the hot side because of actuator failure, it will blow warm/hot even if the refrigerant side is doing its job. Actuators can be difficult to get to as they are behind the dashboard usually. There are also several of them so seeking help from a technician is advised.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: A/C starts blowing cold then gets hot randomly.

A possibility is an electrical problem such as a faulty clutch cycling switch. Also, check to make sure that the electric condenser fans are operational, and cycling properly, as the compressor kicks on and off. Faulty condenser fans, or the...

Q: problem with starter maybe?

Hello. Will be happy to assist you. It does sound like you have an issue with the bendix gear of your starter. Possibly a starter on as last leg and or on its way out. If the starter is bad...

Q: Car makes grinding sound

The alternator is one of the most common problems, as is the idler pulley. These would need to be checked to see if this is the noise. The best way to diagnose the problem is to have a mechanic listen...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...