What You Need To Know About Auto A/C Pressure Switch

Air conditioning high pressure switch

An A/C pressure switch is a critical component of a vehicle’s cooling system. It is less known than other A/C system components like the compressor or condenser. Still, without it, an air conditioning unit cannot operate properly. Read on to learn more about the auto A/C pressure switch’s role and significance in detail!

What Is an A/C Pressure Switch?

An A/C pressure switch is nothing but a safety switch. Every car has dual pressure switches, one for the low-pressure side and other for the high-pressure side. They are both critical to a compressor’s proper functioning. If the pressure becomes too low or too high, the A/C pressure switch will shut down the compressor to prevent any damage. The efficiency and lifespan of an A/C system depend on the pressure switches. Since they shield the compressor and the rest of the system from harm, you must install a new A/C pressure switch if an issue arises.

Why Are A/C Pressure Switches Important?

Despite their small size and simple design, A/C pressure switches are critical in preventing compressor wear and tear. If the refrigerant pressure becomes too high, the compressor can get burned. Similarly, if the refrigerant pressure becomes too low, the compressor can be damaged due to a lack of lubricant. Both of these circumstances can result in compressor failure and expensive repairs. This is why it’s important to examine the switches on a regular basis.

Signs of a Bad A/C Pressure Switch

A defective A/C pressure switch exhibits different warning signs. While some of the signs are more common, others are not. These are some of the common symptoms of a bad A/C pressure switch, which you can also verify by checking trouble codes:

  • The A/C doesn’t turn on
  • The A/C blows warm air
  • The A/C repeatedly turns on and off
  • Strange sounds from the A/C unit
  • The compressor fails to run

How to Confirm a Faulty A/C Pressure Switch?

Before replacing the A/C pressure switch in your car, confirm the problem is with the pressure switch and not with other wirings. You can use the OBD (Onboard Diagnosis System) to decode the error code.

The following are few of the typical OBD error codes linked to a damaged A/C pressure switch:

  • P0745: Issue with the transmission pressure control solenoid “A.
  • P0746: Pressure control solenoid “A” is not working properly or jammed
  • P0747: Pressure control solenoid ‘A’ jammed on DTC trouble code
  • P0748: Fluid pressure mismatch
  • P0749: Voltage issue with the transmission fluid pressure control solenoid

The following codes might indicate a problem with the pressure switch or any other A/C system component:

  • P0530: Malfunctioning A/C refrigerant pressure sensor
  • P0531: A/C system has too little or too high refrigerant
  • P0532: Low refrigerant pressure level
  • P0533: High refrigerant pressure level

What Is the Cost of a New A/C Pressure Switch? 

It depends on your car’s model, make, and year. On average, an A/C pressure switch will likely cost between $20 and $100, and the labor cost will be based on the time and effort it takes to replace it.

The A/C pressure switches are critical to the operation of the A/C system. If you discover any problems with your A/C pressure switches, order them from us to prevent costly repairs!