Why My A/C isn't working
Are Certain OBD2 Features Not Available On My Innova Scanner?

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Summer has arrived, but the A/C has departed from your vehicle. Commuting to work and road trips will not be as pleasant until the issue with the A/C has been resolved. There could be several reasons why your vehicle's A/C isn't functioning properly. An Innova scan tool can help you diagnose what is going on with your A/C. From there, you can decide if you can make the repairs yourself or if you need to see a mechanic. Our scan tools have a free, but optional mobile app that provides what replacement parts are needed for the fix, a link on where to purchase them from, and scheduling repairs with RepairPal.

Here are a few common possibilities:

• Refrigerant leak: The A/C system relies on a refrigerant, such as R-134a, to cool the air. If there is a leak in the system, the refrigerant level may be insufficient, leading to ineffective cooling. A professional technician can inspect the system, locate any leaks, and recharge the refrigerant if necessary.
• Faulty compressor: The A/C compressor is responsible for circulating the refrigerant. If the compressor is not functioning correctly, it can result in a lack of cooling. A trained mechanic can diagnose the compressor and determine if it needs repair or replacement.
• Electrical issue: The A/C system has electrical components, such as fuses, relays, and switches. If there is an electrical problem, such as a blown fuse or a faulty relay, it can prevent the A/C from working properly. Checking the fuses related to the A/C system and ensuring they are intact is a good starting point.
• Blocked or clogged condenser: The condenser, located in front of the radiator, plays a crucial role in releasing heat from the refrigerant. If it becomes blocked by debris, dirt, or bugs, it can inhibit proper cooling. Cleaning the condenser or removing any obstructions may help restore A/C functionality.
• Faulty blower motor or fan: The blower motor and fan help circulate the cooled air into the cabin. If either of these components malfunctions, it can result in reduced or no airflow. A qualified technician can inspect these components and repair or replace them as needed.

1. Receiver/dryer

A receiver is a device to store the refrigerant liquidized by the condenser temporarily, and it supplies the required amount of refrigerant to the evaporator.

A Dryer has a desiccant and strainer in itself, and eliminates foreign matter or moisture in the refrigeration cycle.

If moisture is in the refrigeration cycle, parts in it will corrode or freeze inside the expansion valve, which could cause the clogging.

2. Sight-glass

A sight-glass is an inspection hole used to observe the refrigerant flowing inside the refrigeration cycle and to check the level of the refrigerant.

There are 2 types: one is installed at the outlet of the receiver and the other at the piping between the receiver and the expansion valve.

Generally, when many bubbles are seen from the sight-glass, it means the amount of refrigerant is insufficient, and when no bubbles are seen, the amount is appropriate.

In the case of no refrigerant or excessive refrigerant, no bubbles are seen, so it is necessary to pay attention. In addition, depending on the conditions such as engine speed or refrigerant pressure, even if the level is appropriate, bubbles can be seen.

For sub-cool type condenser, since more refrigerant is filled at the point at which the bubbles disappear, the refrigerant may be insufficient even if it seems normal in the inspection from the sight-glass.

How to use the A/C Pressure Chart?

If you feel that your vehicle’s A/C is not cooling properly, then it's time to take some action. The first thing recommended is to check for the pressure of the refrigerant, and see if the pressure readings of both high side and low side are within the optimum range in the A/C Pressure Chart.

A/C Pressure Chart:

How Much Does A/C Repair Cost?

Some of the most severe problems can be costly, but this can be money well spent when the temperatures are scorching.

Here’s a look at some national average estimates to fix the most common air conditioning issues, courtesy of RepairPal.com. Prices will vary according to the cost of parts for your specific vehicle, local wage rates, and other factors. Estimates do not include taxes and related service requirements.

• System Inspection: Up to $70 
• Refrigerant Recharge: $120 to $155
• Blend Door Actuator Replacement: $325 to $375
• Cabin Air Filter Replacement: Up to $85
• Compressor Replacement: $720 to $950
• Compressor Clutch Replacement: $570 to $620
• Condenser Replacement: $450 to $600
• Condenser Fan Replacement: $385 to $475
• Electronic Control Module Replacement: $380 to $400
• Temperature Sensor Replacement: $320 to $400

Tips for maintaining your A/C

• Run the system for at least 10 minutes each week at its highest fan and lowest temperature setting, even in the year’s coldest months. This basic process helps lubricate the compressor and prevent leaks. While you’re at it, run the defroster for 5-10 minutes to clear the system of any moisture or mildew.
• Change the cabin air filter according to your vehicle’s maintenance schedule.
• Have the refrigerant recharged every two years. This isn’t as easy as the first two steps, but kits are available online with detailed instructions. 
• Finally, don’t hesitate to take the car in for service if the climate control system isn’t working as expected.

HVAC System Diagnosis Chart

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