My wife drove our 2007 Monte Carlo to work, when she started the car and the radio would not come on, no big deal. She went to leave work and her key fob would not unlock the car. So she tried to use the key to manually unlock the car. Key would not turn in the lock cylinder. So she called me, my key fob would not work either. Try my key in door, it wont turn either. swap battery from key fob on my car to make sure no weird dead fob batteries. Still no go. Can see light from cell phone charger in car so didn't even consider a dead car battery.


Leave car for the night.


Next day go with some tools to unlock car and some graphite lubricant. Check fobs again, no go. Spray lubricant in lock cylinder. Neither key will turn cylinder still. get dry pried out enough to get a tool and push door lock button...nothing...try pushing button other way...nothing. am able to get tool on door handle...will not let door open. Do this on both doors with no luck. I was not able to get the tool on the manual door lock switch.


Decide to call lock smith, they are in the car in a matter of minutes. When door is opened...no interior lights...Car battery is dead. Jump car it starts.


All that to ask what might cause the keys to not work in door. Any thoughts?


Sorry for long first post.

 

Same thing happened to me when I first bought my Monte. Original owner had an alarm system installed that was causing all kinds of issues. so I removed it. Not before I got locked out of the car, just like you did. Keys would not unlock door. Locksmith had no trouble getting in...My keys still do not unlock the door, but they work in the ignition. Only thing I can think of is that the ignition switch was replaced at some point and now the keys are mismatched to the door?

 

That would be my guess. I think a locksmith can set the door tumblers for you.