Ricoh FT7770 Service Manual page 577

Service Call 21 -
o The short circuit of the lift sensor connector from the upper
or lower paper feed unit is open for more than 3 seconds.
Disconnect CN203 on the main board.
Is there a short circuit between CN203-B5 (connector) and TP215.
Y N
\
Check and correct the harness and contact.
Are the lift
Y N
I
Replace
Replace the main board.
Service Call 22 -
o The lift sensor from the option tray is open for more than 3
seconds.
Disconnect connector CN204 from the main board.
Is there a short circuit between CN204-B8 (connector) and TP215?
Y N
I
Check and correct the harness and contact.
If the option tray lift signal (CN204-B7) is not correct,
replace the option tray lift sensor.
Paper Feed Unit
sensor signals (CN203-A12, -A14) correct?
the upper/lower tray lift sensor.
Option tray Paper Feed Unit
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