Audio Systems: Chrys. stereo amp.schematic, amp unit, stereo amp

Question
I've been trying to diagnose & repair an amp. : 2000 Chrys. Concorde Issue 1 LH Amp. P/N: PO4760296AC, Date Code : 0070, Supplier: 07910,S/N : T29AJ0070B6003.Finally, replaced amp.unit (located pass. compart. RH kick-panel)stereo now works. I have disassembled the old amp.;can not SEE anything burnt...Would REALLY like to figure out WHAT is wrong...Any ideas on obtaining the proper wiring schematic & test procedures? Thank you for your expertise & time.

Answer
only thing i could do is component to component testing with a good digital meter and a magnifying glass to look at solder connections. as far as schematics, i've never found any for stock units....although base wiring system diagrams can be gotten by buying the dealer manuals for your car from the dealer's source....