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1 9. TROUBLESHOOTING GUIDE
I
CD PART -
CD Function Select
Is power turned ON?
YES
I NO
1
. Check power supply circuitry.
I
1
NO
Does initial reading occur? Check laser circuitry.
F
YES
Check focusing circuitry.
t-
(_ Check disc. -
,
Can disc be played?
I
\
NO
I Check track,ing servo circuitry.
I
-
YES
I 1
NO
Is audio output supplied? Check Audio circuitry.
I
YES
I 1
OK
I
- 30 -
(1) If display LCD lighting is not normal
piYGzq (W'THouT
Dw
1 NO Check voltage in the power
/ NO Power supply circuitry
Do display LCD then light?
W supply circuitry. * defective.
I
YES
1
Is u-COM IC401 reset circuil Reset circuit defective.
normal? Pin @ NO Surrounding circuit defec-
tive.
QV -
YES
1
Is u-COM IC401 C.L.K
terminal Pin @j (OSC) NO C427, C428 defective.
input? X401 defective.
about 0.25psec ee
YES
1
Is IC401 8, @ output
waveform normal? NO Pattern defective.
YES
1
Is IC401 Pin @ output
waveform normal? Pattern defective.
YES
Display defective.
(2) If initial reading is not carried out (with Disc)
NO Is IC401 Pin @output NO
Does disc motor rotate?
waveform normal? Leaf SW contact defective.
t- Connector defective. -
YES Pattern short.
Ic4" @`-I DOOR CLOSE
YES
I
Is RF wave Is tracking servo Is signal output Is signal
IC601 defective.
output? NO operating? NO at TEI? NO output, NO
Connector
Is the lower at IC601
defective.
envelope of RF Pin @?
Pick-up defec-
waveform flat?
tive.
-
T YES
YES
I
YES
Is signal output at tracking output NO IC601
IC601 Pin @? defective.
IC601 Pin @waveform
YES 1 I Pick-up
defective.
Connector
Is rotation normal?
Is there any irregularity in
Does IC701 Pin @(LKFS) as 1 defective.
figure?
frequency? NO
YES
I
Is HF signal normal without 1
dropout?
NO Disc initial reading damaged
w or defective.
c 1
YES
Disc defective.
- 32 -
@I When laser does not light.
I
below signal "L" at IC401
1
YES NO
Has Pick-up returned 3 to 1
.,. NO ~ pd,Egggedfrorn NQ ,,
IC401 defective.
the innermost posrtron.
,
YES YES
Is below signal output at No
IC602 Pin @, @?
. t 1 IC601 defective.
Does pick-up stop after
II
Are detect output input at
having moved to the
IC601 Pin @?
innermost position? IC602
Pin @.
-----------~ PZLSW defective.
Connector defective.
/
tlq IC602 defective.
Does generate about 39 at
IC601 Pin @ LD in IC401 Pin @ No IC601 defective.
(PZ APC)? b Surrounding circuitry defective.
/ '
YES
T NO b Connector defective.
Has laser power source
returned to the Q600?
(Q600 collector voltage about
2.2V) Q600 defective, connector
defective.
Laser defective.
Flow laser current?
Both voltage of Q600 is about YES Laser defective.
NO
1 .OV? e R600M.OV L
b Connector defective, short etc.
4
(I
33 I
@I When laser lights.
Is signal output at focus search NO
Do lenses move up and down? IC601 defective.
terminal?
C614 defective.
YES
IC601 Pin @ (FEI)
YES
1
Is signal output at IC601 Pin
@? NO IC601 defective.
Insert disc and
in the case of
YES
7
I Actuator short.
Connector short.
I
1
check of initial
leading.
Is RF (HF) signal waveform
output? Connector short.
NO
IC601 defective.
YES
-1
The waveform of RF (HF) is
below figure? Turntable height error.
NO
Laser diode degraded.
RF (HF and REF) 0.4V over NO
_/*I
YES
1
Is Fok signal input to IC401 Pin @I
NO
(PFOK)? Pattern defective.
rl
YES
I
34 -
0
YES
I
-
Is FE1 signal output?
IC601 P IC601 defective.
NO
Pick-up defective.
Connector defective.
YES
I
Is FEI signal output at IC601 Pin @
(ISTAT)? NO When Fok focus
IC601 defective.
Servo Conform by
FZC signal.
FEI
SENSE
YES
I
Is Mon signal output by Pattern defective
IC701 Pin @I ? NO between IC701 Pin@.
@ @@and IC4Or.
Is MDP signal output by
IC701 Pin @ ? III,
1111 I
YES
I
IC601, 602 defective.
Has voltage at disc motor? Surrounding circuitry
NO
defective.
YES
_ 1 Disc Motor defective.
p Connector defective.
I
AUDIO CHECK
Power circuit check
\
NO NO
Is output? 1 b Is each voltage normal? * Power source, Pattern check.
,
YES
I
1 Is signal returned at IC701 Pin
@),@?
5v 0 : 88.2kHz
-4
NO IC701 defective
circuitry.
surrounding
OV J-L 8: 4.3218MHz
YES
1
Is signal output at IC702 Pin @ , IC702 defective.
@ ? Surrounding circuitry.
n
YES
r-~~~
J
IS T' at IC401 Pin @ (zDMuT)?
-4
NC IC401 defective.
YES
1
Is "L" at IC701 Pin @?
Pattern defective between IC401
Pin @and IC701 Pin @ .
YES 1
\ v /
Is signal output at lC3Oi Pin @ NC IC301 defective.
@,@@@@@? W Pattern defective.
I
YES
I
r------
Audio check OK.
- 36 I
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