Hitachi P50A202/D8UF, Service Manual

Page: 30 / 92

D8UF
TABLE OF CONTENTS
28
...TROUBLESHOOTING FLOWCHARTS ( fi nished).
P50A402, P50A202 page 2/2
(The following is checking procedure after removing back cover.)
＊
) Connector Pin assignment of Power Supply Unit
[CNPPS] [CN06] [CN23]
1 Audio+17V 1 Vcc+5.1V 1 Va
2 AudioGND 2 GND 2 N.C.
3 +17V 3 Vra 3 Vcc+5.1V
4 GND 4 Vrs 4 GND
5 +5.6V 5 Vcego 5 GND
6 +5.6V 6 Vsago 6 GND
7 GND 7 AC oFF 7 N.C.
8 GND 8 Vs
9 STBY+5V 9 Vs
10 GND
11 AC CloCK
12 PoWER_1
13 PoWER_2
14 AC oFF
15 N.C.
＊
) Power-On control signals for Power Supply Unit
(1) AC power : Supplied Æ PSU outputs STBY+5V.
(2) Power Switch: ON : or Remote Power button : ON
Æ PoWER_1 rises up.
(3) PoWER_1 : High
Æ PSU o5.6V.
and STBY+5V changes from 5.1V to 5.6V.
(4) PoWER_2 : High
Æ PSU o17V and Audio+17V.
(5) Vcego : High
Æ PSU outputs Vcc+5.1V for PDP Module.
(6) Vsago : High
Æ PSU outputs Va and Vs for PDP Module.
(The voltage values of Va and Vs are indicated to the sticker on the PDP Module.)
If any control signal does not rise, PSU cannot output the voltage.
࡮
PoWER_1/2 : not rise ----- Main board trouble
࡮ Vcego/Vsago : not rise ----- PDP Module (Logic board) trouble
However, Vcego rises when PNLRST/CPUgo (P901 [43] at Main board) is High, and
Vsago rises when PNLoN/PDPgo (P901 [42] at Main board) is also High.
B
Check Main board.
A C
[1st] Check Power Supply Unit.
[2nd] Check PDP Module. [1st] Check PDP Module.
[2nd] Check Main board.
Are the following outputs
from Power Supply Unit
all normal ?
Vcc, Va, Vs (
＊
)
No
Yes
Are the following outputs
from Power Supply Unit
all normal ?
STBY+5V, +5.6V,
+17V(
＊
)
No
Yes
[1st] Check Power Supply Unit.
[2nd] Check Main board.