I have a 2003 Accord LX Sedan which I bought about a month ago. OEM radio preset buttons did not work and back speakers did not work. I just installed a new Pioneer aftermarket unit last night hoping that the old unit was the reason the back speakers did not work. Everything works great on the new Pioneer but still no back speakers. I don't have a clue as the where to begin troubleshooting this one. Any suggestions? Thanks.

 

start with checking the rear speaker tinsel leads. they are exposed to the trunk and can be damaged.