chimes

Hi everyone, I've a cobalt 2010 and a couple of months ago my front speaker stopped working (and with it the chimes for seating belt, indicator chimes and so on) but the radio goes fine over the other speakers. So, I don't know how to verify (and which one is the good one) if it's a fuse or...

The front speakers work intermittently. When they work, they both work as do chimes. When not, neither works. There seems to be power to the plug in the door jams but not past the plug towards the speakers when they don't work. The dealer said need to replace both harnesses ($400 + labor) but...