I can probably answer this question, but the terminology has me a bit confused. I think you're asking if the switching is done on the 12 volt feed side or the ground side. When a relay is involved, as is typical with a high-current clutch coil for the compressor, it is almost always done on the power side, and the clutch coil is always grounded near the compressor.
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Monday, January 5th, 2015 AT 2:45 PM