As vehicle owners in many parts of the country begin using their air conditioning systems for the first time this year, some will be surprised to find their A/C system is not functioning properly or isn’t blowing out cold air like the summer past.

The following is a recap of common A/C system problems, followed by real-life A/C system problems from 2003-’05 General Motors SUVs and a poor performing climate system on a Toyota truck.

Causes for A/C Repairs
A/C compressors are usually the most expensive A/C component to replace, followed by condensers and evaporators. So it’s very important to make sure (1) the compressor is really bad and needs to be replaced, (2) the cause of the compressor failure has been identified and fixed so the new compressor does not fail for the same reason, and (3) the new compressor is installed properly and lubricated with the correct type of compressor oil.

The most common cause of compressor failure is inadequate lubrication. This may be the result of a refrigerant leak that allows compressor oil to leak out of the system. Typical leak points are hoses, hose and pipe connections (O-rings and flange gaskets), the evaporator, condenser or the compressor shaft seal. Leak detection dye or an electronic leak detector should be used to find the leak so it can be repaired.

Proper Lubrication and Debris
Lubrication problems can also be caused by a blockage (...