I just came back from vacation and I put my key in my car, I drive a 1993 SC400, and I turn it to the left/right and it doesn't even work!? Like it's not even the right key to the car. The key goes in, but when I turn it to the left or right, it's stuck. Doesn't turn at ALL. So I go over to the passenger side, and it works. I have to unlock the door from the passenger side, then I can open the door on the drivers side. Anyone have any idea why out of the blue my key just doesn't work? Is this a common problem?

 

May be someone try to jammed a screw driver into your driver side key cylinder.

 

The car was parked in my garage so I don't think that would be the culprit. Keyhole isn't messed with or anything. Something must of failed because my hood shocks don't even stay up either. So I need to replace that too.

 

Another common problem is your door actuator/the door lock assembly. It is not hard to replace the actuator,but once you can not open the door to remove the door panel you have to find the way to open the door from the outside.I mean stick a long rod from the outside,a flash light, and try to break the locking mechanism so the door can be open in order to replace the door lock actuator.

 

I unpluged my car battery and to work on my engine and now my doors will lock with factory keyless but will not unlock the doors will lock and unlock from inside and the key. My car alarm will not lock on unlock the doors. The doors lock as soon as I turn the ignition on but will not unlock. Maybe alarm and keyless entry are sending diffrent comands.
To me sound like your actuator is bad.

 

Last time this happened to me was when I accidentally locked the steering rack. I had to unlock it and then I was able to turn on the car. Are you able to turn the steering wheel at all? If you can't then it locked and now you have to unlock it

 

If so, it sounds like the mechanical
connection between the lock cylinder and the door lock is disconnected.
In that case, you would need to remove the door panel and reconnect
the mechanism, or replace whatever is broken.
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