[Dynomite]

Originally Posted by mike100

The schematic isn't complete, but there is tuned L/C on the board- which is more or less tuned to the speaker size. You can't do anything with these except repair them. It's a lot more economical to go aftermarket if everything on the bose has gone bad (there's a tuner box separate or the head unit, then the 4 amps driving proprietary 1 ohm speakers).

As you have no doubt seen on other links to posts, the Nissan units are newer improved versions of the late c4 amps and are a dime-a-dozen and are a cheap way to keep the factory unit going if you like the oem look.

See Bose Speaker Amp Options TIPS

See Bose Speaker Amps

See Easiest way to remove/install Bose CDM (Control Data Module)