Automotive Air Conditioning Information Forum

Hello ,

I have always wondered is it best to turn off a/c compressor - cooling switch before starting your car engine ? By doing it this way does it make it easier on the compressor / car engine ?

On most vehicles, the AC compressor and other accessories are not on the Start circuit, are on the Run circuit only. So it shouldn't matter, but OK to do so if you desire.

Cusser wrote:On most vehicles, the AC compressor and other accessories are not on the Start circuit, are on the Run circuit only. So it shouldn't matter, but OK to do so if you desire.

I'd have thought the same - my car's compressor clutch kicks in about 3-5 seconds after the engine has started.