Phoenix Gold ZX475ti

Ive got this one which partially works, but LF and RR channels have 0.9vDC on them. The other two channels work. On the PCB, only half the LEDs are lighting up indicating those channels are not coming online. I removed the pre-amp board to help service the amp without having the ribbon cables flopping around and the amp still powers with only half the LEDs lit near the drivers away from the heat sync.

Is a schematic floating around for these style amps?