2003 mustang gt only left driver tweeter

[true01blueGT]

2003 mustang gt only left driver tweeter works but everthing dont sometimes when i hit a bump everything sounds good, idk if its bad speaker or bad wire

 

[Neuron]

Only way I know of is to tear into and check the speaker and if good the wiring and if good the head unit( yes I have seen some weird things happening in them).