2000 gmc denali door lock

My boss bought this car from an auction.  The car had an aftermarket alarm but was removed.  The question i have is when i push the lock or the unlock it will only lock.  Had anyone else had this problem.  Also did these cars have a door lock chime?  When i hit the lock or unlock a chime goes off.  Any help will be apreciatied.

Is this problem solely on one door, or do all the doors have this problem?? There's nothing out of the ordinary about the lock system on this truck (type a pos trigger), which 'possibly' eliminates whether or not you pulled something you shouldn't have (bypass module or relay pack). Find the door lock wires (in the door boot) and test each to see if you get anything out of them when you activate the switch. Because it sounds like a switch issue. As for the chime thing, I think 02 and up were databus, so you should hear the chime.G. Rick (aka; Tha "R")

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