What is this sensor chip? AFAIK, there's a pair of switches built into the door lock mechanism. Either the key triggers it or it doesn't. My driver side door only has one working switch -- on the lock side. I unlock the car, open the door and turn the key again to the lock position so the alarm doesn't go off. Bugs the heck out of my wife because she never remembers to give it a second twist.

Sixto
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