Ignition Key Won't Turn.

I got Prius C Two a few months ago. It came with "valet key" only. So, I decided to add a key with the remote. After new key was cut (got a couple visits), I've noticed that my original valet key started working only in one position. It's two-sided key, so, when I insert it one way, it does not turn, when I re-insert it 180 degrees, it turns no problem.

So, now I'm curious, if I got some metal chips within a lock, or did I bent some pins? And if I want to cut another key, how do I specify, which side of the key is good, and which is bad? I read that most Toyota locks have 4 pins on one side, and 3 pins on another.

PS. I tried to oil it with "hard grease" (not WD40). Keys insert with not problem...

 

Thanks for this post, my Prius 2001 at 493K came back in service with flying colors again. I know this post is old, but was thankful I found it, otherwise I was already planning to ditch the car given the mileage. For those read this thread, who is not convinced as to the Priuses realiability should believe that when somebody says "it's one of the most reliable cars they've owned, well, better believe that!"

I did what the-wes instructed and removed a couple of split tumblers (the circular kind, not the cylindrical, is used in these key locks and lo and behold, it's nice and smooth again. It took a while to put back as I mistakenly tried it in and rotated the whole key assembly more than 180 degrees (don't do that!) and end up with the whole assembly stuck in there again, it took me a while to get it out again. But once out, and lessons learned here, I managed to put it back. Thanks again the-wes.