Basic Troubleshooting Guide; Basic Troubleshooting Guide For Traverse Unit; Module P.c.b - Panasonic SA-PT650P Service Manual

22 Basic Troubleshooting Guide

22.1. Basic Troubleshooting Guide for Traverse Unit (DVD Module P.C.B)
Problems
1) Distorted picture or
abnormal sound is head
during the initialization
2) No TOC / Long TOC
3) Disc not spinning
4) Traverse not moving
5) Traverse and spindle
abnormal movement
6) Cannot read the disc but
spindle motor is spinning
- Cannot read CD/DVD
7) Block Noise during play
8) Jitter out of specification
Checking Points
a) Check SDRAM address,
data bus, CLK and other
control signals waveform
b) Check video signals
c) Check audio DAC circuitry
* Compare the above with
OK condition HDMI

module P.C.B.

a) Check motor driver
circuitry (+5V)
b) Check laser drive
circuitry (Voltages &
current)
c) Check LSI IC connection
to motor drive circuitry
*Compare the above with
OK condition HDMI
Module P.C.B.
a) Check connection from
HDMI Module to Traverse
unit
b) Check motor driver
circuitry on the voltages and
control signals
*Compare the above with
OK condition HDMI
Module P.C.B
a) Check laser drive
circuitry (voltages
and current)
- Check CD Laser
Drive
- Check DVD Laser
Drive
* Check voltages and LD
current and compare with
OK condition HDMI
Module P.C.B.
a) Check SDRAM address
and data bus signal
a) Check LD current
b) Check OPU
(Change to other unit and
confirmed operating
condition)
129
Checking Components
IC8051
LB8301, R8321, R8322,
LB8302, R8325, R8326
IC8421
*Check for solder short
and/or component
missing/damaged
IC8251 Pin 8, 21
Q8551, Q8552, Q8561,
Q8562
IC8001 Pin 144 ,145
* Check for solder short
and/or component
missing/damaged
FP8251
IC8251
*Check for solder short
and/or component damaged
Q8551, Q8552, LB8531
(For DVD Laser Drive
current)
Q8561, Q8562, LB8561
(For CD Laser Drive
current)
IC8051
OPU Unit (Traverse unit),
FPC connection
SA-PT650P / SA-PT650PC