T&M SA8200 only 3 channels working!

I have an T&M SA8200 8 channel Solid State Amplifier. It's just lost another Channel - so I have only three channels left. I have been looking online to download a Workshop Manual for this, but can only find a User Manual - which is useless for this problem. Does anyone know where I can download a pdf of the Workshop Manual for this Amplifier, please? Michael