Power steering intermittently stops working

Hello, are you saying your power steering is malfunctioning? This vehicle has Electronic Power steering, there is not fluid involved. There is an electronic motor that controls the steering. Has the check engine light been on at all?
There are multiple sensors that are incorporated into this system. Using a scan tool, the system should be checked for codes. A regular scan tool most likely won't scan this system, it has its own computer that controls it, so it can be any number of things malfunctioning.
Is the power steering having a heavy feeling or hard to turn?
And/or the ESP light on?
There is a Technical Service Bulletin for these types of issues.
It says they are extending the warranty for the Electronic Power Steering control unit 15 years from purchase date.

Hello,

Just to clarify, you are having issue with the power steering not working part of the time.

Does it work normal and all of a sudden gets tight to turns the wheel?

This could be due to a belt slipping on the power steering pulley.

Please let me know little more details of what you are experiencing.
Thank you.

https://www.2carpros.com/articles/power-steering-problems