Patent ID: 7047778

Claim:
A vehicular lock operable by a coded key and having an uncoded state in which the lock is not coded to the key and a coded state in which the lock is coded to the key, the coded state having a locked condition in which the key is not in the lock and an unlocked condition in which the key is in the lock, the vehicular lock comprising: a housing; a barrel located at least partially within the housing and selectively rotatable with respect to the housing; a sidebar located at least partially within the barrel and selectively engagable with the housing to prevent rotation of the barrel with respect to the housing, the sidebar having an engaged position with respect to the housing in which the sidebar prevents the barrel from rotating and a disengaged position with respect to the housing in which the sidebar does not prevent the barrel from rotating; and a plurality of tumblers having a first tumbler portion and a second tumbler portion, the first portion moveable by a key inserted in the lock, the second portion movable into engagement with the first portion, at least one of the first tumbler portions and second tumbler portions movable with respect to another of the first tumbler portions and the second tumbler portions in the uncoded state of the lock and coupled for movement in the coded state of the lock, wherein the first tumbler portions have one of a projection extending away from a side of the first tumbler portion and elongated aperture extending along the first tumbler portion, the second tumbler portion having the other of a projection extending away from the side of the second tumbler portion and an elongated aperture adapted to receive a projection, at least one of the projection and aperture having serrations, the first tumbler portion movable with respect to the second tumbler portion in the uncoded state of the lock and coupled for movement in the coded state of the lock.