how to refresh one component from another component?

Question

Hi i have two components A&B. In A i am having a dropdown which contains car models.In B i am having one more dropdown contain model year.If I am selecting a car from dropdown A the available year associated with that selected car will display.All are working fine but im facing one issue that from B if i am changing any particular year A component not refreshing immediatly .Aftr page reload only am getting the new values.How i can solve this.Ngonint call is not a good way because i am having enough methodes inside that?please help