I have always learned that when you go to remote areas you should have at least a basic knowledge of car repair and depending on the make of car and the area you go to your knowledge should be good to expert.

So your first action should be looking whether you can repair it, with what you have and where you are.

If that is not possible, you go to what the answer by @Gerrit tells you and you use your emergency pack as well as trying to contact people.   
If there might be people in line of sight, even not in direct sight, starting a fire which smokes by day might help.