I have a 2002 Civic EX Coupe. After I arrived at work this morning, I went to lock my car using the remote and it didn't honk after I hit it 2x. So I went back to the car, and I noticed my passenger side door would lock, but my driver's side would not. I tried using the automatic locks in the car, and it wouldn't lock. I also tried just pushing the lock down, and it still wouldn't lock. It was around 20-30 degrees in illinois this morning, and I'm not sure if this has anything to do with it. Can someone please tell me what the problem might be and how much it is to fix?

Thanks. Thanks in advance for the help.

 

my car has the same problem.
Try this little trick:
With the door open, pull the handle like you were trying to open the door, then lock the door.
Sounds dumb, but worked on my car.

 

Probably a bad lock actuator in the driver door. If you're handy, you'll save money by doing job yourself. It's relatively simple after you remove the door panel.

 

To lock the driver's door manually, you must do what Punisher said. Get out of the car and with the door open, hold the outside handle up. Push the inside lock button down. While still holding the handle up, close the door. This is a feature intended to make it harder to lock your keys inside the car.