Suddenly the paddle shifters and the buttons on the steering wheel stopped working?

If there is a loss of steering wheel functionality like button and shifter paddle inputs or LEDs and display not working while the steering angle and pedal inputs are still working, it might be caused by an interrupted or unreliable connection between the base and steering wheel. 

When functions of the steering wheel stop working on a CSL DD or GT DD Pro it's best to check weather the quick release is still properly inserted into the base shaft, for details please check this video: CSL DD / GT DD Pro Quick Release Re-seating - YouTube