It can quickly ruin your day if your car’s AC goes out. Leakage or problems with the compressor are two of the most common causes of broken air conditioning. Your AC may be failing to blow cold if it is not cooling down.
It doesn’t mean you have to live with a stale, uncomfortable car. Neither do you need to depend on the shop for the solution. Finding the right solution is difficult. This guide will help you identify the problem and provide three suggestions before visiting a mechanic. Learn how to fix your car’s AC.
HOW TO DIAGNOSE AC PROBLEMS IN YOUR CAR
1. Is your AC cool but not cold?
If the air conditioner is not blowing cool air but has fans and is on maximum cool:
Make sure that you check the temperature of the condenser and the radiator cooling fans are on when the air conditioning is on.
You should look for any restrictions, such as leaves, bugs, or dirt, that could prevent air from passing through the condenser.
To ensure it is clean, check the cabin filter.
Next, you should always use a manifold gauge to check the pressures within the system. You can find the repair manual for your vehicle or online. Once your gauges are connected, you can begin to observe the AC compressor.
2. Start with the ac compressor
It’s easier to diagnose an air conditioner problem by starting at the compressor.
Turn the engine on, turn on maximum cool, raise the fans, and ensure that the compressor is engaged. This is not the pulley. It’s the centerpiece that connects the compressor shaft to the pulley. Low refrigerant can cause the clutch to engage and disengage once per second. The low-side pressure of your gauge will drop quickly when the clutch engages. Once it reaches a point where the pressure is too low, the clutch will disengage, and then the pressure will rise. The gauge should remain steady as long as the compressor is running.
- To check for voltage reaching the compressor, if the clutch isn’t engaging or the system contains refrigerant, you can use a Voltmeter.
- The clutch could be defective if there is too much voltage.
- If there is no voltage, the cycling button could be defective. The system may not have enough refrigerant to trip the low-pressure cutoff switch, which cycles the compressor.
3. Leaks cause the most problems
The most common problem with an air conditioner system is a leak. Low pressure can indicate a leak.
- The easiest way to detect a leak is with a UVA/C leak detection kit. To find a leak, follow the instructions on the package.
- Verify that all fittings are secure.
- Make sure to inspect the hose manifolds.
- Make sure to inspect the front seal as well as the o rings that seal the pressure switches at the back of some compressors.
- Make sure to check where the Hoses are crimped onto the fittings.
- Verify the Schrader Valves.
You should inspect the area where the UV light is absorbed by the evaporator. Sometimes, oil and dye can be visible.
Note that the dye test will not work if the system temperature is too low or the compressor is not running.
ARE YOU STILL SUSPECT? STILL NOT SURE? CHECK THESE COMPONENTS
AC COMPRESSOR & CLUTCH
An AC compressor is a rotating pump that circulates Freon throughout the system.
Common Problems: It is possible to have leaks in the compressor or one of its seals. The most common cause is particle contamination caused by worn parts within the compressor. Sometimes, the compressor can be rendered inoperable by a failure of the engagement clutch (also known as an AC clutch).
What to look for: Check for refrigerant levels that are low. Look out for system leaks that look oily or green. Leakage or normal wear of internal components. Failed AC clutch. Failed AC clutch due to a blown fuse or bad pressure control switch, dash module, or broken circuit wire. Check and test before you replace it!
The Accumulator/Drier absorbs and collects moisture. Moisture can cause damage to the AC Compressor and other internal components. You may have either an accumulator, receiver, or dryer, depending on the vehicle.
Common Problems: Internal failure that allows desiccant material into the AC system. This stuff can cause serious problems, just like sugar in the gas tank. Over-saturation can cause compressor damage.
AC ORIFICE TUBE / EXPANSION VALVE
The AC expansion tube/orifice tube filters and regulates the refrigerant flow through your air conditioning system. You may have either an expansion valve or an orifice tube, depending on the vehicle.
Common Problems: Contamination can be the primary cause of failure. The expansion device may be at fault if the system pressures are too high or too low. First, make sure the refrigerant levels and fan(s) of the radiator/A/C condenser are correct. Always inspect and test before you replace!
The AC condenser is similar to a radiator, and it works with the radiator fan(s). The hot (gaseous) refrigerant inside the vehicle is cooled by air flowing through the tubes of the AC condenser. This cools the refrigerant to a liquid form, allowing it to enter the core of the evaporator and absorb more heat.
Common Problems: Leakage of refrigerant. Poor cooling can be caused by contamination particles in the AC Compressor, AC Accumulator/Drier, or AC Accumulator/Drier. While inspecting the AC Condenser, check the Radiator/AC cooling fan motor(s).
AC EVAPORATOR CENTER
The AC evaporator is like an ice cube but with holes. It allows hot cabin air to flow through its core and then quickly cools it before blowing it out again. AC heater motor assembly provides cool air from the dash vents.
Common Problems: Leaks due to wear and age are the leading causes of failure. A leak detector can be used to detect leaks. Pay attention to the AC water drain tube. To find a leak, use the tester. If there are larger leaks, a greenish-olive substance could appear in the drain tube.
These resources are intended to be helpful for general maintenance and repairs and should not be relied upon as a substitute for professional assistance. AutoZone believes that the information is correct and current to the best of its knowledge. However, there might be errors, omissions, or misinformation.
For vehicle-specific information, make sure you consult your owner’s guide, a repair manual, an AutoZoner at an area store, and a licensed professional mechanic. For specific information on your vehicle’s diagnostic, repair, and tool requirements, refer to the service manual. Before lifting a vehicle, always chock its wheels. To protect the electrical circuits of the vehicle’s electrical applications, always disconnect the negative battery cable prior to lifting it. Be careful when using automotive batteries. Sulfuric acid can cause skin and clothing burns and blindness. Wear gloves, safety glasses, and other personal protection equipment. Work in well-ventilated areas. If electrolyte gets on clothing or your body, immediately neutralize it with a solution made of baking soda and hot water. When working on your vehicle, don’t wear loose or tied.