i just had some fan work done to my 03 dak.. ie a vicouous fan clutch.. the a/c compressor is disconnected since last june when old one siezed up and we put in a used one but never filled it up or replugged it in.. we drove it since we got it from from dealer on thru to now with no issues or engine light .. so we goto local zoo its parked under a canopy all day we start to leave zoo and its tossing out a 0645 code.. but unit isnt even plugged in is sensor just now realizing its not plugged in or something or anyone have any ideas?

Schuey