Need more information to fix this. It could be as simple as a bit of burnt wiring, or as complex as a clockspring or other issue. You may have to have this diagnosed by a mechanic as you haven't given enough info here to really help solve your problem. It is likely that the AC and the other issues are not related unless corrosion, etc., has set into the fuse box, or a mouse chewed wiring under the hood and shorted all of the items out.
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