Assuming you choose a dealer that is connected to ServiceBeacon, your car dealership will have access to your personal information so that it can do business with you. For example, when you book service online via ServiceBeacon, your contact information is passed to the dealer along with your service requirements.
Aside from your car dealer, no persons or companies will have access to your information. There are some automated services within ServiceBeacon that may need to use your information, such as a dealer locator that locates the dealers nearest to you based on your zip/postal code.