Weirdest thing. 2008 Trailblazer. Key off. AC fan in#1 position. Turned key off 24 hours ago, removed key. Just now heard a fan. Went to truck, AC was blowing with key still off and out of the ignition switch. Been around truck severally for that 24 hours, and it just started. What gives? Guess there's a haint around here? Update: it just did it again.