Ive got a 2004 sedan with the Bose system, today my driver door speaker stoped working.

could it be just a short or is it blown?
What can i do to find the problem?

 

pop door panel off, look at speaker, take multimeter set to ohms (resistance) see if it is reading 2-4ohms. if it is then get a 9V battery take 2 shielded wires tape then to ends of the of battery. then tap them (don't leave them on) the speaker contacts. if the speakers moves and crackles it's likely still good.
If it works then you've got either a wiring issue or an amp issue.