Panasonic UB-5838C, Service Manual

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37
5.3. Others
Phenomenon Possible Cause Check Point
Nothing is indicated on
the display. 1. DC power from the POWER Board
is not correctly supplied. 1. Restart this unit (Panaboard) and then check whether this
phenomenon is reproduced.
2. Check the connection between the POWER Board and
CONTROL Board (CN6).
3. Check the following signals on the CONTROL Board.
(1) CL13: + 24 V
(2) CL14: + 5 V
(3) CL15: + 3.3 V
4. Check the soldering condition of R420 on the CONTROL
Board.
5. Replace faulty parts, CONTROL Board, or POWER Board
2. CONTROL Board does not work
properly. 1. Restart this unit (Panaboard) and then check whether this
phenomenon is reproduced.
2. Check the soldering conditions of CPU (IC4), ROM (IC2),
and RAM (IC3) on the CONTROL Board.
3. Check the following signals on the CONTROL Board.
(1) X1-3rd pin, IC5-6th pin: 48 MHz
(2) CL17: + 1.8 V
(3) L55: + 3.3 V
(4) CL3: 100 MHz
(5) IC15-1st pin (Reset signal): + 3.3 V
4. Replace faulty parts or CONTROL Board.
3. PANEL Board does not work
properly, or its board connections to
some other parts are not proper to
display. 1. Restart this unit (Panaboard) and then check whether this
phenomenon is reproduced.
2. Check the connection between CN700 (PANEL Board)
and CN7 (CONTROL Board).
3. Check the connection between CN701 (PANEL Board)
and LCD.
4. Check the soldering conditions of IC700 and IC701 on the
PANEL Board.
5. Check the soldering conditions of IC16, IC17, and IC20 on
the CONTROL Board.
6. Check the following signals on the PANEL Board.
(1) CL728: + 5.0 V
(2) CL729: + 3.3 V
7. Replace faulty parts, CONTROL Board, or PANEL Board.
Key operation is not
recognized. 1. A problem with the key mechanism 1. Restart this unit (Panaboard) and then check whether this
phenomenon is reproduced.
2. Check that pushing each key comes into contact with the
switch block.
3. Replace the key, panel sheet, or PANEL Board.
2. A problem with key operating circuit 1. Check the connection between CN700 (PANEL Board)
and CN7 (CONTROL Board).
2. Check the mechanical and soldering conditions of SW700
to SW703 on the PANEL Board.
3. Check the soldering conditions of the following parts on
the PANEL Board.
→
IC704, IC703, R740 to R742, and R744
4. Check the soldering conditions of the following parts on
the CONTROL Board.
→
IC16, IC17, and IC20
5. Replace faulty parts, CONTROL Board, or PANEL Board.
When pushing the
Start/Stop Key to perform
the copy function,
Screen-feed does not
start. A Device for outputting the scanned
image is not specified. 1. Insert a USB Flash Memory Device or SD Memory Card
into the unit (Panaboard), or connect a PC or a printer to
the unit.
Then confirm whether the device illustration you need is
displayed on the LCD.
A static electricity on the screen
surface prevents the screen from
advancing. 1. Turn off the unit and then slowly move the screen by hand.