Interior door lock isn't locking
 

ive had this problem for a while now and I'm just now attending to it. Whenever I try to lock the door on the inside and it doesn't lock on the drivers side but it locks on the passenger side. It also locks with the key as well. I changed the power lock actuator or whatever you call it but it's still doing it. I'm starting to think its the door handle itself

Re: Interior door lock isn't locking
 

Look for broken wires in the drivers door jamb.
Use a test light on the power lock motor wiring.

Also, if you don't have the drivers door closed when you try to lock it, you have to pull out on one of the handles in order for the lock mechanism to work.

Re: Interior door lock isn't locking
 

Which year and model is your car? I just went through the same thing on my '97 EX coupe. You have to make sure the actuator's arm hole lines up with the small plastic post within the latch. I ended up removing the latch on the driver's side so I could physically see the plastic post. While latch out of car I line up actuator arm hole and latch post, screwed down actuator and re-installed it as one unit.. works fine since.

If that's not the issue than most likely the central lock module needs to be replaced ... blue box in driver's door above speaker... pull from junkyard.
As Ezone stated broken wires are always a possibility as well.

Re: Interior door lock isn't locking
 

on my 2003 honda civic ex, i replaced the driver's side inside door handle because that chrome stuff was peeling away. looked like it was easy enough to do...i unscrewed the old handle, the switch bracket, and removed that little plastic clip that held the lever that, i guess goes to the door latch/lock. i replaced everything, thought i had the plastic clip thing properly attached to the l on the lever..and it won't work right now...and, now, when i hit the power door locks, all 3 other doors work fine, but the driver's side door lock won't move properly.. it wants to move, but it's catching somewhere. then when i pull on the inside door handle it loosens up and works, but then goes back to being stuck after that. also, when it is stuck in the locked postion, i tried to unlock it from the outside using the key, ansd the key won't turn in the lock. i was really casreful , i thought , not to miss anything or bend anything... now what can i do..the switch seems ok...what did i do to it..it's worked fine forever.

Re: Interior door lock isn't locking
 

Shut the door or pull out on either handle, then you can lock or unlock it. (this is described in your owners manual too)

The drivers door is designed so you have to make multiple mistakes before locking your keys inside the car.