Ricoh FT7770 Service Manual page 541

7) Lines at irregular intervals
Is toner clogged in the cleaning unit?
Y N
I
Check the blade cleaner.
- Is it straight?
- Does it contact the cleaning blade properly?
- Does it move correctly?
Y N
Correct or replace any defective parts.
Check the optics thermoswitch and the cleaning thermoswitch.
Replace if defective.
8) Light black line(s)
Clean the PCC corona wire.
13-17
30 April, '89