To successfully complete CARS you need to achieve a score of 80% or more across the five quizzes.  You can check whether you have passed CARS by selecting 'Grade Centre' from the top menu of the CARS Content page in the LMS. 

If your highest score is less than 80% you can go back to the quizzes and try again as many times as you like until the unit's completion date.

Check your LMS for the required completion date of the CARS unit you are enrolled in.