So you've probably had this warning light come on before, and if you haven't...you will. It typically will trigger when you're making a turn. If you're at all a stickler for having a clean dash like I am, it will drive you nuts. It can also cause your turn signal to not automatically reset after your turn. This is also wildly annoying. The dealer, and most repair shops, will tell you that you have to replace the instrument cluster in your steering column. The part will run you about $600, give or take. Tack on about another $200 in labor if you have them replace it for you. Those prices are nothing to shrug at, at least for me, so I did a little research to see if there were any other options. I ran across this post that has detailed instructions on how to fix it:
Now, it's entirely possible that you may need a new instrument cluster. But why not try out this repair first? Just to summarize, the issue is that the optical disk within the steering column is not being read properly. For me, and most others on forums that I read, this is due to the crystallization of some residue on the disk. Note that I did not have to do all the steps in the guide. Specifically, those near the end that require re-soldering of electrical components on the electrical board. After you take apart the steering column and get to the optical disk, some rubbing alcohol and q-tips is all you need to clean it up. I did this fix about 2 months ago and the issue has not returned. So with this fairly simple DIY, I saved (re-purposed to a new FMIC) a bunch of money and got my sanity back.
(For your convenience, I added the above post as a PDF: Steering Angle Sensor Fix)
Please add a comment with the results of your fix or any other info that might be helpful to others, thanks!