Lock cylinder stuck

The ignition lock cylinder seems to be stuck. We put the key in and it won't rotate far enough to start the car. I'm thinking the issue is that one of the pins is sticking. Can I use WD40 inside the keyhole? If not, what should I use?

2001 Carolla

i have used wd-40 before but most recommend grafite powder as it isn't supposed to attract dust.the grafite can be bought in a bottle with a tip end on it.

I used the graphite powder in the end. Unfortunatly, it didn't help much. I am going to go out and pick up a new lock cylinder for it tomorrow. I'm just annoyed that I can't get one with the same key, and I'm to cheep to get it rekeyed by a lock smith.

I figured out how to switch the cylinder:

1: remove the screw on the bottom of the steering column
2: turn the wheel to the right and remove the screw that is under the steering wheel
3: turn to the left and remove the screw
4: pull off the panel that covers the sterring column
5: turn the key to "ac" if you haven't allready
there is a little button on the bottom of the cylinder. push it in while pulling the cylinder out with the key
6: put the key in the new cylineder and turn it to "ac"
7 slip the new cylindder in
8: put the column back together and replace the screws.

better put both keys[the old one and new one] on the same keyring or keyrings.so you can open the doors and then crank it up.