Digital BW, The Print

Hello,

I have problem with blocked nozzles for the black Eboni.
All 5 nozzles fires off good except for the black.
I have tried to find in the service manual how to do the stronger 
cleaning process but I cant find how you get to it from the manual.
Can someone guide me how to get to the KK1 and KK2 cleaning (page 
211 in service manual) Or any advice to clear this clogg. Normal 
cleaning does not seems to help.

Regards
Soren