If your example of your brother is typical of the type of thing that sets him off then it would appear that being self-absorbed or flagrantly ignoring responsibilities bugs him. (As it did me when mine were your age). Here’s what family counseling taught me:
When you are the parent of a teen, you have to be clear about responsibilities and consequences, and be consistent in delivering consequences. In the example above, brother goes to the girlfriend, leaving dirty dishes, leaves you with younger brother all day, the role of the parent is to say, I expect you to wash the dishes and tidy up the kitchen before you go to Meghan’s house, or you will [lose the use of your car, insert consequence of parent’s choice]. If you do not do what you are asked to do by the time requested, it is reasonable to negotiate a new time before the time approaches, and then deliver on what you agree to.
Kids should not have to guess what is expected, parents should not have to yell. When you are responsible for something as an adult, and you don’t deliver, there are consequences. If you’re supposed to do something by a certain time, and you choose to watch television, go to the girlfriend’s, whatever, instead of doing what is expected of you, then you are choosing to lose car priviledges, or whatever the consequence is. Your parent is not being mean, but rather being consistent. If he says do x by y time or Q will happen, and you choose to watch television instead, then you are in essence choosing Q.
As teens become older, their extraneous time commitments need to be factored in. Saying what you need done, and asking when it can be completed by is a courtesy that should be extended to your children after a certain age, especially if they’ve demonstrated that they don’t need to be told. If you agree to clean the basement on Saturday, that comes before going to the movies with friends. In order to go to the movies with friends, you get up earlier on Saturday and take care of what you committed to do.