From your description sounds like steering angle sensor. Sounds like you don't have a scanner which is a requirement to maintain an X5 (or very deep wallet).

Google how to reset the steering angle sensor if that resets the light plan on getting a new one or the refurbish kit on eBay. But: don't do it until you can confirm with a 2nd level scanner like foxwell nt 520. Don't be fooled by higher numbers the 6xx tools are less powerful.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)