Panasonic FP-7742 User manual

Service Manual
ORDER NO. OED9607318C1
Plain Paper Copier
FP-7742/7750
© 1996 Matsushita Electric Industrial Co., Ltd.
All rights reserved. Unauthorized copying and
distribution is a violation of law.
FP-7742/7750 Service Manual
(Field Service)

*WARNING
This service information is designed for experienced repair technicians only and
is not designed for use by the general public.
It does not contain warnings or cautions to advise non-technical individuals of
potential dangers in attempting to service a product.
Productspoweredbyelectricityshouldbeservicedorrepairedonlybyexperienced
professional technicians. Any attempt to service or repair the product or products
dealt with in this service information by anyone else could result serious injury or
death.
This equipment has been tested and found to comply with the limits for a Class A
digital device, pursuant to part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interference when the equipment
is operated in a commercial environment. This equipment generates, uses, and
can radiate radio frequency energy and, if not installed and used in accordance
with the instruction manual, may cause harmful interference to radio
communications. Operation of this equipment in a residential area is likely to
cause harmful interference in which case the user will be required to correct the
interference at his/her own expense.
Any unauthorized changes or modifications to this equipment would void the
users authority to operate this device.
For U.S.A.
This manual was developed and is supplied to authorized servicing dealers by
Panasonic Communications & Systems Co. for the sole purpose of providing
information necessary for the equipment's proper support. It is intended that this
information be confidential and may not be reproduced without prior written consent
from Panasonic Communications & Systems Co. Panasonic Communications &
Systems Co. reserves that right to change any information enclosed herein without
prior notification.

Rear Jacket Unpacking/
Installation
Troubleshooting
PCB Connector and
Signal Information
Component
Location
Preventive
Maintenance
Contents / Index
I. Component Location
1.1 Inner View.......................................................................................... 1-1
1.2 Fan/Motor Location............................................................................ 1-2
1.3 Sensor Location................................................................................. 1-3
1.4 Solenoid/Clutch/Discharge Lamp Location ........................................ 1-4
1.5 PCB Location..................................................................................... 1-5
II. Preventive Maintenance
2.1 Maintenance Chart ............................................................................ 2-1
III. PCB Connector and Signal Information
3.1 Main CPU PCB .................................................................................. 3-1
3.2 Control Panel PCB........................................................................... 3-16
3.3 Paper Feed Driver PCB ................................................................... 3-24
3.4 Automatic Duplex Unit Driver PCB .................................................. 3-28
3.5 Low Voltage Power Supply PCB ..................................................... 3-32
3.6 AC Driver PCB................................................................................. 3-45
IV. Troubleshooting
4.1 Service Mode..................................................................................... 4-1
(1) Service mode function............................................................. 4-1
(2) Service mode procedure ......................................................... 4-2
(3) F4 mode .................................................................................. 4-4
(4) F5 mode copier function programming ................................. 4-16
(5) F6 mode adjustment and programming ................................ 4-21
(6) F7 mode electronic counter................................................... 4-26
(7) F8 mode copier operation adjustment................................... 4-27
4.2 Self-diagnostics/Machine Malfunctions............................................ 4-29
(1) User error .............................................................................. 4-29
(2) Paper jam.............................................................................. 4-35
(3) Machine error ........................................................................ 4-38
4.3 User Preset Mode............................................................................ 4-53
V. Unpacking/Installation
5.1 Installation Requirements .................................................................. 5-1
5.2 Contents Check ................................................................................. 5-1
5.3 Unpacking.......................................................................................... 5-1
5.4 Installation Procedure ........................................................................ 5-2
5.5 Adjustment......................................................................................... 5-7

6. Rear Jacket
6.1 Electrical Schematic Diagram
(1) Schematic Diagram
(2) Main CPU PCB
(3) Control Panel PCB
(4) Paper Feed Driver PCB
(5) Automatic Duplex Unit Driver PCB
(6) Low Voltage Power Supply PCB
(7) AC Driver PCB
(8) Automatic Original Density Sensor PCB
(9) Copy Density Sensor PCB
(10) LED Array PCB

Rear Jacket Unpacking/
Installation
Troubleshooting
PCB Connector and
Signal Information
Component
Location
Preventive
Maintenance
Caution: Danger of explosion if battery is incorrectly replaced.
Replace only with the same or equivalent type recommended by the manufacturer.
Dispose of used batteries according to the manufacturer’s instructions.

1-1
Component
Location
I. Component Location
1. 1 Inner View
12 3456
78910111213
1. Fuser area cover
2. Toner bottle
3. Drum unit
4. Developer unit
5. Toner hopper unit
6. Developer release lever
7. Waste toner bottle
8. Total counter
9. Manual paper feed knob
(Feed unit)
10. Paper transport handle
11. Transfer/Separation corona
and corona cleaner
12. Paper transport unit
13. Manual paper feed knob
(Fuser unit)
SV711

1-2
1. 2 Fan/Motor Location
SV705
Mirror stepping
motor
Optics drive
motor
Lens stepping
motor
Developer
cooling fan
Toner bottle
motor
Dust collecting
fan
ADU paper length
guide motor
ADU paper width
guide motor
ADU drive motor
Optics fan
Optics fan
Main motor
Optics fan
Exhaust fan
Lifting motor
(lower stage)
Suction/Ozone
fan

1-3
Component
Location
1. 3 Sensor Location
Mirror home position
Exposure lamp
home position
Platen cover
open/close
Platen cover
angle
SV706
AE (Automatic original
density sensor)
Original size
ADU
detection
Toner density
Copy density
ADU paper
length
ADU paper
pass 1
Paper exit
Lens home
position
Front cover
open/close
ADU paper width Paper level
(lower stage)
ADU paper
detection
ADU paper
pass 2
Registration
roller paper pass Paper detection
(lower stage)
Bottom plate upper limit
sensor (lower stage)
Middle roller paper pass
(upper/lower stage)
Waste toner
bottle
Total counter
Bypass paper
detection
Bypass paper size
Toner level
Toner bottle
home position
Paper feed cover
open/close

1-4
1. 4 Solenoid/Clutch/Discharge lamp Location
SV703
Paper feed clutch
Registration roller clutch
Discharge lamp
Middle roller clutch
Bypass pick-up solenoid
Paper feed clutch (lower stage)
Separation
solenoid
Paper exit
solenoid
Power switch
Door switch
ADU clutch
Pick-up solenoid (lower stage)
Recycle solenoid

1-5
Component
Location
1. 5 PCB Location
HVPS (High voltage
power supply)
LED array
Control panel 4
Control panel CPU
Control panel 3
Paper feed driver
LVPS (Low voltage
power supply)
AC driver
Main CPU
Automatic duplex
unit driver
SV704

2-1
Preventive Maintenance
II. Preventive Maintenance
2.1 Maintenance chart
1) Replacement
Item Service Part number Q'ty per Maintenance cycle (x 1000)
unit 120 240 360 480 600
Paper Paper feed roller FFPMA0541 2 X
feed DFP Roller FFPMA0541 2 X
unit Pick-up roller FFPMA0542 2 X
Cleaning sheet FFPHK0951 2 X
Registration roller FFPMA0539 1 Replace at 1,080,000 copies
Registration roller bearing FFPMQ0559 2 Replace at 1,080,000 copies
Middle roller FFPMA0545 1 Replace at 1,200,000 copies
Torque limiter (Bypass) FFPXQ24H00 1 Replace at 1,200,000 copies
Torque limiter (Copier) FFPXQ04H00 1 Replace at 1,200,000 copies
Developer Cleaning blade FFPHK0942 1 X
unit Wire FFPXL05H00 1 X
Developer FQ-ZK20 1 X
Drum FQ-HK20 1 X
Side seal (Front) FFPXG51H00 1 X
Side seal (Rear) FFPXG50H00 1 X
Spacer ring (Front) FFPHQ0059 1 X
Spacer ring (Rear) FFPHQ0060 1 X
Waste toner bottle FFPQA0165 1 X
Toner dispersion cover FFPXG08H00 1 X
Magnetic roller stopper (Front) FFPXG06H00 1 X
Magnetic roller stopper (Rear) FFPXG07H00 1 X
Drum separation finger FFPLK0332 1 X

2-2
Item Service Part number Q'ty per Maintenance cycle (x 1000)
unit 120 240 360 480 600
Fuser Separation finger (Upper) FFPLK0331 5 X
unit Separation finger (Lower) FFPLK0231 4 X
Thermister FFPBL0015 1 X
Fuser lamp (850W) H12V085WN2A 1 X
Cleaning web FFPKM01343 1 X
Cleaning web pressure roller FFPMA0470 1 Replace at 1,200,000 copies
Heat roller (FP-7750) FFPMA0564 1 X
Heat roller (FP-7742) FFPMA0566 1 X
Heat roller bearing FFPMQ0572 2 X
Heat roller gear FFPMF1057 1 X
Fuser entry guide (lower) FFPKF1308 1 Replace at 1,200,000 copies
Pressure roller FFPMA0565 1 X
Pressure roller bearing FFPMQ0573 2 X
Heat-insulating bushing FFPJF0034 2 X
Optics Exposure lamp E08V025WN2A 1 X
unit Dust protection filter FFPJD0038 2 X
Filter A FFPGB0022 1 X
Filter B FFPGB0023 1 X
Main Suction/Ozone filter FFPHJ0039 1 X
body Ozone filter 1 FFPHJ0038 1 X
Ozone filter 5 FFPHJ0042 1 X
Dust protection filter FFPHJ0030 1 X
Discharge lamp
PQ24V10WMG2 1X
Transfer/Separation corona FFPVL01H01 1 X
Wire 1 FFPXL04H00 1 X
Wire 2 FFPXL05H00 1 X
Wire cleaner FFPXL01H00 1 X
ADU Paper feed roller FFPMA0558 1 X
DFP roller FFPMA0559 1 X
F/R Mylar FFPXD07J00 1 X
Storage roller FFPMA0557 2 X

3-1
PCB Connector and
Signal Information
III. PCB Connector and Signal Information
3.1 Main CPU PCB
(CN1)
Pin Signal Destination Status Function No. Name
6 EPACNT LVPS PCB VL control signal
CN117-5
7 PGND LVPS PCB 0V Power ground
CN117-4
8 PGND LVPS PCB 0V Power ground
CN117-3
9 VP LVPS PCB DC+24V power supply
CN117-2
10 VP LVPS PCB DC+24V power supply
CN117-1
0V
OFF ON
0V
24V
0V
24V
(CN1)
Pin Signal Destination Status Function No. Name
1 ZCRS LVPS PCB Zero cross signal
CN117-10
2 VLC LVPS PCB DC+5V power supply
CN117-9
3 GND LVPS PCB 0V Ground
CN117-8
4 GND LVPS PCB 0V Ground
CN117-7
5 VL LVPS PCB DC+5V power supply
CN117-6
Pulse
0V
5V
0V
5V

3-2
0V
24V
(CN2)
Pin Signal Destination Status Function No. Name
1 PGND ADU driver PCB 0V Power ground
CN651-2
2 VP ADU driver PCB DC+24V power supply
CN651-1
3 PGND ADU driver PCB 0V Power ground
CN651-4
4 VP ADU driver PCB DC+24V power supply
CN651-3
5 F32OUT ADU driver PCB 32 bit data output
CN651-5 signal
6 QLTH ADU driver PCB Date transfer latch
CN651-9 signal
7 F32CLK ADU driver PCB Data transfer/receive
CN651-11 clock signal
8 QLD ADU driver PCB Data receive shift/load
CN651-13 control signal
9 DXIN ADU driver PCB 32 bit data receive
CN651-15 input signal
10 DXMCA ADU driver PCB ADU drive motor
CN651-10 drive signal A
Pulse
Pulse
Pulse
0V
24V
(CN2)
Pin Signal Destination Status Function No. Name
11 DXMCAB ADU driver PCB ADU drive motor
CN651-12 drive signal A
12 DXMCB ADU driver PCB ADU drive motor
CN651-14 drive signal B
13 DXMCBB ADU driver PCB ADU drive motor
CN651-16 drive signal B
14 PSLSN ADU driver PCB Length paper guide
CN651-6 sensor signal
15 PSWSN ADU driver PCB Width paper guide
CN651-8 sensor signal
16 DXENB ADU driver PCB Data transfer output
CN651-7 enable signal
17 VL ADU driver PCB DC+5V power supply
CN651-17
18 GND ADU driver PCB 0V Ground
CN651-18
19 VL ADU tray sensor DC+5V power supply
CN-1
20 DXOPSN ADU tray sensor ADU tray detecting
CN-2 signal
0V
5V
Close 5V
Open
0V
5V
0V
ON 5V
ON 5V
0V
Pulse
Pulse
Pulse
ON 5V
0V
Pulse 5V
0V
Pulse 32
0V
Load5V
Shift

3-3
PCB Connector and
Signal Information
(CN2)
Pin Signal Destination Status Function No. Name
21 GND ADU tray sensor 0V DC+5
CN-3 power supply
22 ADSUL ADU driver PCB ADU detecting signal
CN2-24
23 OUT2 ADU driver PCB Output spare
24 GND ADU driver PCB 0V Ground
CN2-22
(CN3)
Pin Signal Destination Status Function No. Name
1 F32OUT System console 32 bit data transfer
driverCN601-5 output signal or LCC driver
PCB CN562-5
2 FENB System console 32 bit data output
driverCN601-6 enable signal or LCC driver PCB CN562-6
3 OQLTH System console 32 bit data transfer
driverCN601-7 latch signal or LCC driver
PCB CN562-7
4 F32CLK System console 32 bit data transfer/
driverCN601-8 receive clock signal or LCC driver PCB CN562-8
5 OQLD System console 32 bit data receive
driverCN601-9 shift/load control or LCC driver signal
PCB CN562-9 (for system console)
6 LCCLD LCC driver 32 bit data receive
CN562-10 shift/load control
signal
(for LCC)
7 OQIN System console 32 bit data receive
driverCN601-11 input signal or LCC driver PCBCN562-11
Pulse
Pulse
Pulse 32
5V
Detect
0V
ON 5V
LoadShift
LoadShift

3-4
(CN3)
Pin Signal Destination Status Function No. Name
8 QMCLK System console Drive motor clock signal
driver CN601-12 (System console or LCC) or LCC driver
PCB CN562-12
9 VL System console DC+5V power supply
driver CN601-13 or LCC driver PCB CN562-13
10 GND System console 0V Ground
driver CN601-14 or LCC driver
PCB CN562-14
11 IN6 Spare output
12 OUT1 spare input
Pulse 5V
0V
0V
5V
(CN4)
Pin Signal Destination Status Function No. Name
1 PGND Copier paper 0V Power ground
feed driver
CN601-3,4
2 VP Copier paper DC+24V power supply
feed driver CN601-1,2
3 F32OUT Copier paper 32 bit data transfer
feed driver output signal CN601-5
4 QLTH Copier paper 32 bit data transfer
feed driver latch signal
CN601-7
5 F32CLK Copier paper 32 bit data transfer/
feed driver receive clock signal CN601-8
6 QLD Copier paper 32 bit data receive
feed driver shift/load control
CN601-9 signal
7 QIN Copier paper 32 bit data receive
feed driver input signal CN601-11
8 FENB Copier paper 32 bit data transfer
feed driver enable signal
CN601-6
9 VL Copier paper DC+5V power supply
feed driver CN601-12
10 GND Copier paper 0V Ground
feed driver CN601-13
0V
24V
Pulse
Pulse
Pulse
0V
ON 5V
0V
5V
Pulse 32
0V
Load5V
Shift

3-5
PCB Connector and
Signal Information
(CN5)
Pin Signal Destination Status Function No. Name
11 GND Paper feed 0V Ground
cover sensor
CN-3
12 GND Bypass paper 0V Ground
detecting sensor CN-3
13 VL
Registration roller
DC+5V power supply
paper pass sensor (rear) CN-1
14 VL
Registration roller
DC+5V power supply
paper pass sensor (front) CN-1
15 RRSN2
Registration roller
Paper detecting signal
paper pass sensor (rear) CN-2
16 RRSN
Registration roller
Paper detecting signal
paper pass sensor (front) CN-2
17 GND
Registration roller
0V Ground
paper pass sensor (rear) CN-3
18 GND
Registration roller
0V Ground
paper pass sensor (front) CN-3
(CN5)
Pin Signal Destination Status Function No. Name
1 VP Bypass paper DC+24Vpower supply
feed clutch CN-1
2 HFCR Bypass paper Clutch ON/OFF signal
feed clutch CN-2
3 VP Bypass DC+24Vpower supply
registration roller
clutch CN-1
4 RRCR Bypass Clutch ON/OFF signal
registration roller clutch CN-2
5 VP Bypass paper DC+24V powersupply
feed solenoid CN-1
6 HFSOL Bypass paper Solenoid ON/OFF signal
feed solenoid
CN-2
7 VL Paper feed DC+5Vpower supply
cover sensor CN-1
8 VL Bypass paper DC+5Vpowersupply
detecting sensor
CN-1
9 QDOSN Paper feed Cover open/close
cover sensor detecting signal CN-2
10 HPESN Bypass paper Paper detecting signal
detecting sensor CN-2
5V
Detect
5V
Detect
0V
5V
0V
5V
0V
24V
0V
24V
5V
Detect
Close 5V
Open
0V
5V
0V
5V
0V
24V
ON
ON
ON

3-6
(CN7)
Pin Signal Destination Status Function No. Name
1 GND Copy density 0V Ground
sensor CN-1
2 CDSN2 Copy density Analog Paper base tone
sensor CN-2 0 to 5V detecting signal
3 VCDS Copy density Sensor ON/OFF signal
sensor CN-3
4 CDSN1 Copy density Analog Copy density detecting
sensor CN-4 0 to 5V signal
5 GOPSW1 Developer unit Developer unit detecting
signal
6 TDREF Toner density Analog Toner density gain
sensor CN-1 0 to 8.5V adjustment output signal
7 VP Toner density DC+24V power supply
sensor CN-2
8 TDSN Toner density Analog Toner density detecting
sensor CN-3 0 to 5V signal
9 GND Toner density 0V Ground
sensor CN-4
10 GOPSW2 Developer unit 0V Ground
(CN6)
Pin Signal Destination Status Function No. Name
1 VL Bypass paper DC+5V power supply
size sensor 3
CN-1
2 HPSSN3 Bypass paper Paper size detecting
size sensor 3 signal CN-2
3 GND Bypass paper 0V Ground
size sensor 3 CN-3
4 VL Bypass paper DC+5V power supply
size sensor 2
CN-1
5 HPSSN2 Bypass paper Paper size detecting
size sensor 2 signal CN-2
6 GND Bypass paper 0V Ground
size sensor 2
CN-3
7 VL Bypass paper DC+5V power supply
size sensor 1 CN-1
8 HPSSN1 Bypass paper Paper size detecting
size sensor 1 signal
CN-2
9 GND Bypass paper 0V Ground
size sensor 1 CN-3
0V
5V
0V
5V
0V
5V
5V
Detect
5V
Detect
5V
Detect
5V
ON 0V
5V
Not detect
0V
24V

3-7
PCB Connector and
Signal Information
(CN7)
Pin Signal Destination Status Function No. Name
11 RCSOL Recycle solenoid Solenoid ON/OFF signal
CN-2
12 PGND — 0V Power ground 13 TH1 Thermistor Analog Fuser temperature
CN-1 5 to 2.7V detecting signal
14 TH2 Thermistor 0V Fuser temperature
CN-2 detecting signal
(CN8)
Pin Signal Destination Status Function No. Name
1 OZFM Suction/Ozone Fan drive signal
fan CN-1
2 DDFM Developer cooling Fan drive signal
fan CN-1
3 OZFL Suction/Ozone Fan lock detecting
fan CN-2 signal
4 DDFL Developer cooling Fan lock detecting
fan CN-2 signal
5 PGND Suction/Ozone 0V Power ground
fan CN-3
6 PGND Developer cooling 0V Power ground
fan CN-3
7 SCFM Dust collection Fan drive signal
fan CN-1
8—
9 SCFL Dust collection Fan lock detecting
fan CN-2 signal
10 VP Middle roller DC+24V power supply
clutch CN-1
24V
ON 0V
24V
ON 0V
24V
ON 0V
0V
Lock 5V
0V
Lock 5V
0V
24V
0V
Lock 5V
0V
ON 24V