Epson 10600 not printing Black and Cyan

[pacart]

We have an Epson 10600 and it won't print Black or Cyan.

when the machine starts up i get the "Nozzle Check Error", then i run the regular cleaning and print out a nozzle check sheet, but no black or cyan.

I have also gone into the diagnostic menu and done the more powerful cleaning, i think it is all the "SSLC B/C" or something like that. So i have done this now 4 times over a 3 week period and nothing is working.

Ok, so we have the technicians manual and my boss wants our pressman to tear into this thing and fix it.

Anything else we can try before we tear into it and is it really a good idea for someone to do this who has never done it?