Ricoh FT7770 Service Manual page 527

3)
Clean the transfer corona wire, and make sure the wire tension
spring is the correct one. (Do not mix up the transfer and the
separation wire springs.)
Adjust the transfer corona current.
Does the quenching lamp energize?
Y N
Is there 485 volts ac between CN315-3 and CN315-4?
Y N
Does CN222-8 drop from +24 volts to ground?
Y
Replace the power supply unit.
Replace the quenching lamp.
Is the charge corona wire properly installed?
Y N
o Install the charge corona wire correctly.
o Replace any defective parts.
N
I
o Check the connector and harness.
o Replace the dc drive board.
13-3
30 April, '89