left side speakers do not work on 2008 Honda CR-V

Left side speakers do not work. To replace harness & speakers is $650. Dealer said they were corroded.

Asked by for the 2008 Honda CR-V
its probably not that there corroded but that either the speakers dont work or the left side of the stereo outputs are fried try hookng up the left and right sides to the right outputs on the stereo and if the speakers work then its the stereo if they dont work its the speakers