I am having the exact same issue. 2005 federal Elise, no locking problems until last week. Pressing the lock button on the remote or center stack will wiggle the lock plungers (up, almost like they are being unlocked again) but not lower them to locked position. Repeated presses will arm/unarm the alarm and immobilizer as it should but the lock plungers never go down. Operating the plungers by hand works fine. (Once locked by hand, both the remote and center button will unlock the plungers.) Dragon, please let us know if you find a fix.