Panasonic FP-7818 Service Manual & Parts Manual page 113

(1) U0: Key counter failure or Access code number was not input
*The copier does not indicate READY TO COPY when the key is inserted.
Is the key inserted correctly?
YES
Is CN119-2 connected to CN-2?
or
Is CN119-4 contact to CN-4?
YES
*Access code number was not input.
Input access code number.
(2) U1: Front cover failure
*The copier does not indicate READY TO COPY when the front cover is closed.
Is the front cover closed securely?
YES
Is DC24V detected on CN851-1,2
(of LVPS PCB) when the front cover is
opened and closed?
(3) U4: Sorter failure (option)
*The copier does not indicate READY TO COPY when the sorter is installed.
Is the sorter closed securely?
YES
Does J3-5 (output signal of Sorter CPU)
change when the sorter interlock
switch is turned ON and OFF?
(4) U5: Duplex unit failure
*The copier does not indicate READY TO COPY when the duplex unit is installed.
Is the duplex unit tray inserted
securely? YES
Does CN2-19, 20, 21 (output signal of
CPU) change when duplex unit tray
is removed and installed?
5-36
NO Re-insert the key.
NO CN119-2, 4 of the CPU is defective.
The key counter connection is defective.
NO Close the front cover securely.
NO The CN851 and CN205 (of AC driver PCB)
connectors are defective.
The CN16 (of CPU PCB) is disconnected
NO Close the sorter securely.
NO Adjust the sorter interlock switch of sorter.
The sorter interlock switch is defective.
(Refer to sorter service manual.)
NO Insert the duplex unit tray securely.
NO Check DC5V of tray detecting sensor.
Detected: Tray detecting sensor defective.
Not detected: Check all DC5V lines.