There is not much you can do unless you can park the vehicle somewhere else. This can be very bad for your car if they start chewing on the wiring bundles and other components. This can get very expensive very fast. Squirrels can also be a problem but they can’t enter the vehicle interior as quickly as a mouse can. I have heard of people putting mothballs and/or charcoal in their vehicles but I just don’t think they are very effective.