First, I believe you have a couple different problems. The first thing that should be done is have the computer scanned. If the check engine light is on, it has a trouble code stored in the computer. Many nationally recognized parts stores will do it for free.
Next, the battery drain is a problem. What to do is follow the directions listed at this site under the "How To" section listed at the top of the page. If there is a draw, remove one fuse at a time until the draw stops and you then have isolated the problem circuit.
As far as the vents, they are actuated by engine vacuum. Most likely there is a vacuum leak under the dash. Check for that. If you are lucky, you may hear a hissing sound with the engine running.
Finally, (and I'll shut up), you have me wondering about the storm. I question if the vehicle was struck by lightening and blew out one of the diodes in the alternator. That would explaine the electrical draw with the key off. You may want to have the alternator tested at the parts store.
Let me know what you find.
Joe
Friday, July 17th, 2020 AT 10:24 AM
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