Wireing Diagram for '91 maxima w/ Bose?

I'm pretty familiar with this and can tell you there are four wires going to each amp module that are next to each Proprietary Bose speaker (1 OHM Impedance).   One wire is Ground,  one is AMP_Turn_ON/Amp Power, and the other two are the proprietary signal wires (Not Speaker level and Not Line Level).   Because the Bose system is NON-STANDARD in every aspect,  If you are hooking up a different head unit, you will need to purchase a BOSE adaptor ( http://www.peripheral-aamp.com/periph_products/line_output_convert.htm)    As far as checking the rear speakers,  you can first measure across the speaker coil to make sure their not fried.   Also, you can check for 12V at the 4 pin connector to make sure it's getting the Turn On/ Power.   If those two things are ok, then it's possible that the AMP Module is bad.    Looks like Peripheral (link above) just started selling replacement BOSE amp modules in case you need replacement(s)  (Rather pricey though!) .