Q: Do the compressor supposed to always be turning if it is not turned on

asked by on

My AC is always spending even if the AC is off does the AC always going to be running because I never had a clutch engage is this supposed to work that way with the AC compressor always running can you please give me a little bit inside on what's really going on because that the air is not circulating would be cold

My car has 167000 miles.
My car has an automatic transmission.

If the A/C switch in the passenger compartment is turned off, any air delivered by the in-dash blower should simply be the same temperature as the passenger compartment, that is not chilled. If you have the A/C switch off and yet cold air is being delivered, that means there is an electrical problem that is causing the system to remain on when it is supposed to be off.


If you are looking at the pulley side of the physical compressor on the vehicle, the external pulley will ALWAYS be turning when the engine is running and so you might mistakenly think the A/C is on when in fact all that is turning is the pulley. When you turn the A/C system "on", a clutch behind the pulley mates the pulley to the compressor itself and it is ONLY at that point that the compressor turns and begins the vapor-compression cycle that creates cooled air in the passenger compartment. If you look at the center of the pulley, when the a/c is off, the central portion of the pulley should be stationary. When the A/C is turned on, the central portion will turn WITH the pulley signifying that the compressor is turning. If you want to have your vehicle’s A/C system checked out and evaluated, please request a comprehensive vehicle a/c system diagnostic. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. Do the compressor supposed to always be turning if it is not turned on

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: How long does it take to put on an ac compressor in a Hyuandai sonota 03 automatic

According to service prodedures, it calls for about 3.9 hours to complete this job which includes replacing the a/c compressor as well as the refridgerant in the system.

Q: Temperature goes into the red zone during slow driving or idling

Hi there. If this occurred right after the work was performed then it is possible that there is air still stuck in the cooling system, but from what you are explaining with the AC, it sounds more like a cooling...

Q: Car stalls and won't stay started.

I am going to need more info to diagnose this problem. Does the car cut off every time even when you give it gas or does it cut off only when it idles? I would have a technician diagnose your...

Related articles

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...
P0052 OBD-II Trouble Code: HO2S Heater Control Circuit High (Bank 2 Sensor 1)
P0052 code definition HO2S Heater Control Circuit High (Bank 2 Sensor 1) What the...
Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...