6) How do you know if the compressor is working, am I supposed to hear it or something? The belts dont seem to be loose or have slack.
Turn the key to run, one position short of starting, that'll get you the required juice. Then with the engine off, turn on the A/C (or have an assistant do it while you stand at the front of the engine). You should hear a solid clunk as the A/C clutch engages. If you know where the compressor sits and can see it, you can also watch the clutch action. If no clunk or clutch movement it could be an electrical problem or a bad clutch. If it makes the sound or you can see it engage try it with the engine running.
Once the engine is running you won't be able to hear it, but if you can see the compressor you can watch it. Does it stay engaged?
Just trying to give you a starting point.
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2012 VW Jetta Sportwagon TDI...at least its a diesel
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