How to Diagnose a Non Working Air Conditioning in a Car

Step-by-Step Guide

1. 1

   Step 1: Turn the air conditioning on while the car is running.

   The air conditioner won’t run properly unless your engine is running.
   
   The best setting for diagnosis is “fresh air” (not recirculated) with the air blowing out of the center vents in the dash and the AC turned on.
   
   Start with the fan speed turned to its highest setting.
   
   If your car has a “Max AC” setting, select that option.
2. 2

   Step 2: Listen for unusual noises coming from the AC.

   Noise could indicate that there is a problem with your compressor and that it needs repair or replacing. , You will need to know if the air is cold, room temperature, or hotter than the air around it.
   
   Also note if it starts cold but turns warmer, or if it is usually warm but blows cold intermittently. , Turn the air pressure to the high and low settings and see if the airflow changes like it normally does. , If there are unusual smells, you could have a leak.
   
   You may also need to change your cabin air filter. , Check your owner’s manual for the location of your car’s fuse panel, as it may be under the hood, in the trunk, or even in the driver’s foot well area.
   
   A blown fuse can cause your AC to stop working.
3. 3

   Step 3: Feel the air coming out of the vents.

4. 4

   Step 4: Notice the air pressure.

5. 5

   Step 5: Smell the air coming from the vents.

6. 6

   Step 6: Inspect your car’s fuses.

Detailed Guide

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