Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. What Sensors in the AC Tell the Car If the System Is Working or Not?

What Sensors in the AC Tell the Car If the System Is Working or Not?

ac malfunction sensor

The average car today contains a bewildering range of sensors that feed information to various computers to monitor everything from air intake to emissions and engine timing. Your car’s air conditioning system also contains a couple of sensors that manage operation. However, unlike oxygen sensors, MAP sensors and others on your car, they don’t feed information to the computer. You can’t “pull a code” on an air conditioner malfunction.

Air conditioning components

There are two primary components that manage the operation of your car’s air conditioning system. The first and most important is the AC compressor. This component is responsible for pressurizing the system during operation. It also adjusts based on your input – when you change the temperature in the cabin through the HVAC control panel. The clutch operates the compressor based on your settings (but it doesn’t really “sense” whether the system is working or not).

The second component is the clutch cycling switch. This is a safety switch designed to keep the system off if there is not enough refrigerant for safe operation. It’s also designed to monitor the temperature inside your car’s evaporator core to ensure that they don’t drop low enough to freeze the entire core (which would stop AC operation).

Both of these components play a role in temperature monitoring and control, but neither of them communicates this information to the car’s computer. Diagnosing an automotive air conditioner problem will require a professional diagnosis of the symptoms (blowing hot air, not blowing at all, noise from the compressor, etc.), and then a complete inspection of the entire system coupled with a check of refrigerant levels, often with a special UV dye to detect leaks.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

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...
Auto Safety Tips
Driving is more than a way to get from point A to point B. Owning and driving a car can also be a highly enjoyable experience. Whether a person is driving...

Related questions

Q: Hot air coming out of AC

Hi. What you might be feeling run is the blower motor. The blower is a different system from the air conditioning. The air conditioning is what actually blows the cold air in your vehicle. The most common cause of an...

Q: What would cause my AC and heater to not work in my 1994 BMW 525i

Hello. If both of these have not worked since the transmission was replaced then I would start by checking all of the connections that were taken off during the replacement. It is possible that there is a bad ground connection....

Q: How do I use the max air conditioning?

The max air conditioning feature is an extra powerful version of the air conditioning, and can be used in extremely hot weather conditions, or when you need to cool the car in a hurry. To use the max air conditioning...