Failure to turn would be an interesting trigger - if you have velocity and are at maximum commanded steering but are not achieving your yaw rate one of two things has happened:
1) Your steering is broken
2) You are understeering (front wheels have lost traction either from turning too far, braking too hard, or accelerating too much)
Without direct feedback it's hard to tell which.
You fix understeer by reducing steering input until you regain traction or transferring weight to the front wheels (or reducing throttle in a FWD car).
One option would be to start reducing speed. You will either regain traction and start getting the yaw you need (if you're understeering), or you'll eventually stop (which is the best response to broken steering). That logic would be the simplest.