Skip the auto shop - Our mechanics make house calls

Symptoms of a Bad or Failing Refrigerant Pressure Switch (Sensor)

refrigerant pressure sensor

The refrigerant pressure switch monitors the pressure in the air conditioning system to ensure it is operating properly. If the pressure gets too low, the switch turns off the air conditioning system. This saves the compressor from running without lubrication and sends a signal that there is a error in the AC system. There are a few symptoms you should look for if you suspect a bad or failing refrigerant pressure switch:

1. Air conditioning works intermittently

When you turn the air conditioning on, does it seem to cool the vehicle down then stop working? Or does it not work all of the time, just at random times? This means the switch may not be working correctly or have an intermittent failure. As soon as this happens, contact a professional mechanic to have your refrigerant pressure switch replaced so you can be comfortable in your vehicle.

2. Air conditioning not working properly

The air conditioning in your vehicle may not seem to get cool enough, causing you to be uncomfortable on a hot day. This can be caused by many factors, and one is a failing refrigerant pressure switch sensor. In hot summer months this can be a safety concern if the outside temperature gets too hot. A mechanic can properly diagnose the issue, whether it is the switch or a low charge in the refrigerant.

3. Noise coming from the AC system

If a high pitched sound comes from the air conditioning system when it is on, this is a sign the pressure switch may be going bad. The switch could be rattling against different parts in the engine compartment, so it is important to have this looked at before other parts are damaged.

4. Blowing warm air

If no cool air comes out at all, it could be a switch problem or another issue within the air conditioning system such as low refrigerant. A mechanic will check the pressure in the system to ensure it has the correct reading. If it is too high or too low, the sensor is most likely failing. In addition, they can read any codes the computer puts out to positively diagnose the problem.

If your air conditioner is not working properly, noises are coming from the system, or it is blowing warm air, contact a professional mechanic. The refrigerant pressure sensor switch is an important part of keeping you comfortable on hot summer days so it should be repaired as soon as possible.

YourMechanic makes getting repairs to your refrigerant pressure sensor easy by coming to your home or office to diagnose or fix issues. You can book a service online 24/7. YourMechanic’s qualified technicians are also available for any questions that may arise.

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

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

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

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.


Post a question and get free advice from our certified mechanics.


More related articles

P0121 OBD-II Trouble Code: TPS "A" Circuit Range Performance Problem
P0121 code definition Throttle Pedal Position Sensor/Switch (TPS) A Circuit Range Performance Problem What the P0121 code means P0121 is a generic OBD-II code which indicates that the Engine Control...
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 P0052 code means This code is seen when the Engine Control Module (ECM) tries to control the...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance Related Trouble Codes: P2158: Vehicle Speed Sensor B P2160: Vehicle Speed Sensor B Circuit Low P2161:...

Related questions

Q: location of knock sensors

The knock sensors are on opposite sides of the engine. Bank 1 is just above the oil drain plug, on the engine block, at the front of the engine. Bank 2 is on the back side of the engine, in...

Q: Annoying noise when I set the AC

It sound to me you are have an issue with the temperature electronic blend door actuator that controls the temperature coming out of the vents of your A/C. To properly diagnose this, YourMechanic would have to scan your truck's computer...

Q: Car slowed down, bolted, and check engine light appeared

Hi there. You have an internal transmission failure. I have seen this a few times on this vehicle. Most of the time the valve body in the transmission just needs to be replaced, but other times it is the transmission...