All plungers work fine except the driver side one that works intermittently .I can use the key to lock the Door ,The plunger does go down but the door wont lock .The Alarm gets activated when I lock and unlock the driver side Door .Everything seems to work fine but If I open the door without using the key ,it opens up ,the Alarm goes off .Awhile back the Alarm would go off by itself during the day ,I would had to run ,unlock the door to disengage it .That has happened lately though . Can it be a bad Lock ?????