Ricoh FT7770 Service Manual page 544

30 April, '89
I
Replace the dc drive board.
o Check and readjust the charge corona current.
o Perform developer mixing using SP 1-1.
o Clean or replace the cleaning brush.
o Clean the edge of the cleaning blade.
o Check that the PCC wire is properly installed, and clean the
wire.
o Check that the edge of the blade cleaner is straight and the
movement of the blade cleaner is smooth. If not, correct or
replace any defective parts.
If the problem was not resolved, perform the following:
o Replace the cleaning blade.
o Check and readjust the PCC current.
o Check and replace the quenching lamp.
o Replace the drum.
2) Dirty background appears
after making many solid
copies.
Mix the developer for 2 minutes using SP 1-1.
3) Dirty background with
negative image
Does the cleaning solenoid energize?
Y N
I
Is there power to the cleaning solenoid (CN304-B12) one
second after the main switch is turned on?
Y N
I
Replace the dc drive board.
Replace the cleaning solenoid.
13-20