Trouble Shooting - Hitachi C43-FD5000 Service Manual

TROUBLE SHOOTING

TROUBLE SHOOTING
1. No raster and no power (How to check LED's Diagnosis)
(Signal PWB)
Is Voltage
at pin(16) of I001
3.3V?
NO
YES
(Signal PWB)
Is Voltage
at pin(59) of I001
"H"?
YES
Check
Q027, Q028,
PPS3, Q902
S901
etc.
Check
I009, I001
Check
I501 pin(37)
-H out,
I503 pin(31)
NO
-DEF Hvcc
etc.
Check
T702, R748,
NO
R730
etc.
No
Raster
NO
(Signal PWB)
Is Voltage
at pin(7) of I001
NO
"AC CLOCK in"?
YES
Check
I001
ON
Check
E907,
etc.
(Power Supply PWB)
Check
D911, R906,
NO
R907, C911
(Power Supply PWB)
Check
I901, D901,
NO
R902
(Deflection PWB)
Is base Voltage
Of Q709 normal?
YES
(Deflection PWB)
Are Voltages
At both ends of T702
(primary side)
normal?
Check
YES
Check
Q777, QH01,
T701, TH01
etc.
(Power Supply PWB)
Is Power LED
NO
(D913,Green)
"ON"?
YES
(Power Supply PWB)
Is click sound
of Relay(S901)
heard?
Check
U901, D902,
YES
NO
Check
Q001, Q002,
I902, D906
(Power Supply PWB)
Does Red LED
(D912) "ON","BLINK"
BLINK
or "OFF"?
1. Turn OFF the power SW.
OFF 2. Wait for 3 seconds.
3. Turn ON again after several
Is Voltage at
pin(4) of I901
14V-20V?
YES
Has Fuse F903
blown?
YES
NO Appear with (6) and (5)
Check
I901, D911,
Check
D910, R908,
R909, R910
R911
Replace F903
Check
SW+115V line SW+28V line
E907, D932, E904, D922,
D925, Q777, etc.
QH01, Q701,
TH01, T701
etc.
51
PWB connecter
(PPS5) open.
(Power Supply PWB)
Is Power LED
NO
etc.
(D913,Green)
Check
etc.
seconds,and observe
green LEDs carefully.
(Power Supply PWB)
Are 4 Green LEDs
NO
turned OFF at the
same time?
YES
(Power Supply PWB)
Does raster
Of PPD4 shorted?
Find LED(s) that is
Turned dark or OFF
YES
Earlier than the others.
Q903, Q904,
etc.
Check Check
SW+5.5V line
D955, I905,
etc.
"ON"?
YES
SBY+5V line
I009, I001,
etc.
Audio line
D956, E901,
D915, IAA1,
etc.