Car Air Conditioner Not Working

Troubleshooting: Car Air Conditioner Not Working? Here’s What to Do

Is your car air conditioner not working and keeping you cool on those hot summer drives when you need them the most? Don’t be concerned! We’ve got your back. In this article, we’ll look at the vexing problem of a broken or malfunctioning car air conditioner.

We will look at the most typical reasons for this issue. Understanding the underlying reason is the first step toward a solution. You’ll be able to identify and solve the problem, guaranteeing your car’s AC system blasts cold air once again, armed with practical recommendations and professional assistance.

So, without further ado, let us go straight into the content. 

Why Your CAR Air Conditioner not Working Properly

Car AC Not Working

There could be a variety of answers to the question, “Why is my car’s air conditioner not working?” We’ve compiled a list of factors for your consideration:

Refrigerant Leak

A refrigerant leak in your vehicle’s air conditioning system might cause it to malfunction. Small breaks in the line or other components might allow the refrigerant to escape. Automobile air conditioning systems can leak due to worn-out components, moisture contamination, corrosion, physical damage from an accident, or road debris.

To resolve this issue, perform these procedures to detect and repair refrigerant leaks:

  • Spray the leak detection can into the air conditioning system after connecting it to the low side service port.
  • If you notice any leaks, you must take the car to a repair shop to get them repaired by a specialist.
  • If there are no leaks, there might be a lack of refrigerant.

Cooling Fans Are Broken

If the cooling fans fail, your car’s air conditioner will malfunction. No air will flow out of the vents if there is an issue with the fans. Cooling fans might cease operating effectively for various causes, including blown fuses, an electrical short, or being fractured by road debris.

  • First, check the fuse or circuit breaker to determine whether it is blown or tripped. 
  • Then, look for symptoms of damage, burnout, or blockage in the fan motor, blower motor resistor or module, cabin air filter, and electrical connections. 
  • If the fan is still not operating, you may have an issue with the compressor, which is responsible for circulating the refrigerant throughout the system and producing cold air.

Problem With the Compressor

The compressor is the heart of the car’s air conditioning system. It circulates the refrigerant through the system, compressing it from gas to liquid. If the compressor is not operating properly, it might alter the flow and pressure of the refrigerant, reducing the system’s cooling capability. 

The compressor has the potential to overheat, make loud noises, or leak refrigerant, harming other system parts. Several factors, such as:

  • Faulty components
  • Insufficient lubrication
  • electrical problems
  • Pollution may be the root of a compressor issue.

To fix the problem, you might have to swap out the compressor or fix the broken parts. In case you wonder how much it costs to replace a car ac compressor, I have written a blog post about it. You can read it here.

Something Wrong With Your Condenser

The AC condenser is a crucial part of the car’s air conditioning system. It cools the compressor’s high-pressure vapor refrigerant, converting it to a high-pressure liquid. The condenser is placed close to the front of the vehicle, where leaks and damage are possible.

Among the warning signals of a broken or inoperable AC condenser are the following:

  • Warm air coming from the vents: A faulty or leaky condenser won’t be able to sufficiently chill the refrigerant, which will cause warm air to come through the vents.
  • Bad odor from vents: If the condenser or any other portion of the AC system is not draining moisture effectively, mold and bacteria can form, resulting in a foul stench from the vents.
  • Leaking AC refrigerant: If the condenser or any of the AC components nearby are leaking refrigerant, you may notice a decrease in cooling effectiveness and a hissing or bubbling sound from the leak.
  • Dashboard warning lights:  Some vehicles are equipped with sensors that monitor the pressure and temperature of the air conditioning system. A warning light on the dashboard will illuminate if there is a problem with the condenser or another system component.
  • Idling engine overheating: If the condenser is clogged with dirt or debris, it can impede airflow through the radiator, causing the engine to overheat.

Electrical Problem

Car air conditioning is electrically controlled. The system may malfunction due to electrical problems such as frayed wires, blown fuses, or a malfunctioning temperature sensor. The following are some signs of electrical issues:

  • No power to the AC system: A blown fuse, a damaged relay, or a defective switch may all be to blame if the AC system does not turn on at all.
  • Intermittent cooling or no cooling: A loose or broken wire, a malfunctioning sensor, or a defective compressor clutch might all be to blame for the AC system’s intermittent cooling or complete lack of cooling.
  • Random AC system shutdown: If the AC unit turns off while it is operating, there may be a short circuit, a malfunctioning thermostat, or a broken pressure switch.

AC Settings

Car Air Conditioner setting

The AC settings are the controls that allow you to change the temperature, fan speed, air direction, and mode of the AC system. When the settings aren’t functioning properly or are configured incorrectly, the AC system may occasionally experience issues and cause your car ac does not work. For instance:

  • The AC system will only sufficiently cool the air if the temperature setting is set enough.
  • The air conditioning system won’t circulate enough air through the vents if the fan speed setting is too low.
  • The AC system will only send the air to the intended region of the cabin if the air direction setting is correct.
  • The AC system won’t use the compressor or condenser to chill the air if the mode setting is off.

Low AC Freon

The refrigerant that moves through the car’s air conditioning system and absorbs interior heat is called freon. The compressor compresses the freon, the condenser cools, the expansion valve expands, and the evaporator evaporates. For the AC system to operate properly, the freon level is essential. The AC system may have many issues if the freon level is low. Following are a few signs of low freon:

  • Warm air flowing from vents:  If the freon level is insufficient, the AC system won’t be able to sufficiently chill the air, which will cause warm air to come from the vents.
  • AC clutch not engaging: The pressure switch won’t engage the compressor clutch if the freon level is too low, which prevents the compressor from starting and pressuring the system. By glancing at the front of the compressor and seeing whether it spins with the auxiliary belt when the air conditioner is turned on, you can determine if the clutch is in operation.
  • Leaking AC system: If you detect any leakage from the AC system, such as oily residue, a white cloud, a hissing sound, or a freon odor, it signifies that you have a low freon level as a result of a leak in the seals, hose, fittings, or other components. By applying soapy water to the suspicious regions and watching for bubbles, you may check for leaks.
  • Low gauge readings: If you have a manifold gauge set, connect it to the high-side and low-side service ports to check the pressure in the AC system. The pressure measurements should fall within a specified range depending on the surrounding temperature and the AC settings. It indicates low freon levels if the measurements are too low.
  • Low sight glass reading: When you switch on the air conditioning, if your automobile has a sight glass on the receiver-drier or accumulator, you may use it to check the freon level. The sight glass should display a clear, foam- and bubble-free liquid refrigerant. You have a low freon level if you notice bubbles or foam.

These are a few possible reasons why car AC is not working.

If you still need help identifying the problem, it is better to consult a mechanic and get your vehicle checked. 

More Scenarios When Car AC also may not work

As a car owner, you are concerned about your car’s health. Till yet we have discussed a lot of reasons why the car AC is not working. So let us dive deeper and take some scenarios when your car Ac may not work. 

Car Air Conditioner not working after winter.

After the winter, if the car’s air conditioner isn’t operating, it may have been damaged by the cold. Once warmer weather hits, fragile or broken parts like valves, seals, or hoses may cause poor AC performance. Before the start of the hot season, it is advised to have your AC system tested and serviced to solve any potential problems.

Car Air Conditioner not working in hot weather.

When it’s hot outside, and the car air conditioner won’t turn on, the AC system is under added stress. When it’s hot outside, if your car’s air conditioner doesn’t effectively chill the air, it may be a sign of low refrigerant levels, a broken compressor, or ineffective cooling fan operation. Identifying and resolving these problems might be aided by consulting a qualified technician.

Car Air Conditioner is not working while idling

When your car is stopped or idling for a long time, the air conditioning system may find it difficult to maintain constant cooling. Reduced airflow over the condenser, which releases heat, may cause this. Low refrigerant levels, defective condensers, or problems with cooling fans might be the root of the problem. While idle, the AC’s performance can be enhanced by having the system examined and fixing these problems.

Symptoms of Car Air Conditioner Not Working

We have understood why the car ac is not working. Here are the symptoms observed when your car ac is not working. 

Warm Air Blowing from Vents

Your air conditioner should be blowing cold air if it is operating properly. Instead, if warm air enters through the vents, there is a problem. Low refrigerant levels, a broken compressor, a blocked condenser, or a broken expansion valve are examples of potential reasons. A qualified inspection is advised to identify the problem and fix it.

No Air Blowing from Vents

If no air blows out of the vents when the air conditioner is switched on, there may be an issue with the blower motor or the fan. Other potential causes include a busted blower motor resistor, a blown fuse, or a damaged switch. An HVAC specialist can find the underlying issue and make the required corrections to restore the airflow.

How to Fix If Your Car AC is not cooling properly

fixing Car Air Conditioner not working

Here is a guide that can help you fix your air conditioner. It is always recommended to consult an expert if it is difficult for you to deal independently. 

Check the cabin air filter

The cabin air filter is typically positioned under the dashboard or behind the glove box. It cleans the air before it reaches the cabin and the air conditioner. The airflow and cooling effectiveness of the AC may be compromised if it is unclean or blocked. You must take the glove box or dashboard cover off to inspect the filter. Then, you may remove it and check it for dirt or debris. If it’s filthy, you may either replace it with a new one or clean it with a soft brush or a vacuum.

Check the refrigerant/freon levels

Low refrigerant levels might result in the air conditioner blowing warm air or not cooling the interior sufficiently. You need a pressure gauge compatible with the kind of refrigerant in your car to check the refrigerant level. 

  • Find the low-pressure and high-pressure service ports on the AC system by opening the hood. 
  • Push the pressure gauge firmly into the low-pressure port until it clicks to secure it.
  • Set the AC to the coldest setting and the fastest fan speed before starting the vehicle. Wait for the system to stabilize for a few minutes.
  • Read the pressure gauge and contrast it with the suggested pressure range for your vehicle.

Check the cooling fans

The condenser, a rectangular component that resembles a small radiator, is next to the cooling fans. As the refrigerant moves through the condenser, the cooling fans remove heat. The AC system may overheat or stop operating if the cooling fans malfunction.

You must start the engine and adjust the AC to the coldest setting and the fastest fan speed before inspecting the cooling fans. Wait for the system to stabilize for a few minutes. 

Next, verify if both fans spin equally fast and forcefully on the condenser’s front. Otherwise, you can have an issue with either one of them or both.

Check the compressor

You must inspect the compressor’s front to see whether it has a clutch that engages and disengages when the air conditioner is turned on and off. The clutch, which is a metal plate, links the auxiliary belt-driven pulley and the compressor. The compressor should spin alongside the pulley when the clutch is engaged. When the clutch is released, the compressor ought to halt. Before checking the clutch, you must start the engine and adjust the AC to the coldest setting and the fastest fan speed. 

Wait for the system to stabilize for a few minutes. Next, you must check the front of the compressor to determine if the clutch is rotating alongside the pulley. If not, the clutch or the electrical system that regulates it might be malfunctioning. You may also test the clutch by connecting a cable from the battery to the connection on the compressor. A loud click indicates that the clutch is operating correctly. If not, a replacement could be necessary.

Check the electrical system

Examine the electrical system that controls and powers the AC components to troubleshoot a car air conditioner that isn’t functioning properly. The battery, fuse box, wiring, switches, relays, and sensors are all included in this system. To evaluate the electrical system, take the following actions:

  • A battery check
  • fuses box examination
  • Wiring analysis
  • Switch inspection
  • Relay evaluation

Frequently Asked Questions

Why did my AC just suddenly stop working?

Your air conditioner could quit working unexpectedly for several reasons. 

  • Blown fuse
  • Tripped circuit breaker
  • Broken compressor
  • Broken thermostat
  • Refrigerant leak

It is advised to speak with a qualified HVAC specialist who can pinpoint the root of the issue and provide an exact diagnosis and solution.

Why is my car air conditioner not blowing cold air?

There might be a number of causes for the air conditioner in your car to not be pumping cold air. Low refrigerant levels, a broken compressor, a blocked condenser, a bad expansion valve, or problems with the cooling fans might all be to blame. 

Will AC still work if the thermostat is broken?

Depending on the issue and the kind of thermostat, the AC may or may not operate if the thermostat is damaged. The thermostat manages the coolant flow to regulate engine temperature. The engine may overheat if the thermostat is jammed closed, prompting the computer to turn off the AC compressor and lessen the thermal strain on the engine. The AC blower motor depends on the signal from the thermostat to work. Thus, if the thermostat is jammed open, it might make the engine run excessively cold. However, the AC cannot even be affected if the thermostat is operational but improperly adjusted.

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In conclusion, a number of things can go wrong with your car’s air conditioner, including refrigerant leaks, damaged cooling fans, compressor difficulties, condenser problems, electrical issues, and improper AC settings. 

The performance of an AC unit might also be affected by certain circumstances like post-winter, hot weather, or idle situations. You may take the necessary actions to address the problem by identifying signs like warm air or no air coming through vents. 

Maintaining maximum AC performance necessitates routine inspections of the cabin air filter, refrigerant levels, cooling fans, compressor, and electrical system. Remember that complicated repairs can need expert assistance. Maintaining your car’s air conditioning system can guarantee a comfortable driving experience regardless of the weather.

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