CHINA TV 14"NORMAL PCB
8873CSCNG 7EK4
EHT BSC25-T1010A
VERTICAL IC LA78040
SOUND IC CV203
TRANSISTOR POWER SUPPLY
Standby problem
1.Power on/Check EHT supply voltage---ok.
2.Check H DRIVER voltage-----ok.
3.Check memory IC voltage voltage---ok.
4.Check memory ic SCL voltage---nil.
5.Check memory IC SDA voltage----nil.
6.Power off/Open memory IC pin SCL,SDA.
7.Power on/Check power on memory IC supply voltage---ok.
8.Check memory IC SCL pin voltage-----nil.
9.Check memory IC SDA pin voltage-----nil.
10.Power off/Open main IC SCL, SDA pin voltage-----nil.
11.Power on/check SCL voltage to PCB---ok.
12.Check SDA voltage to PCB----nil.
13.Check SCL voltage to tuner---ok.
14.Check SDA voltage to tuner---nil.
15.Power off/Open SDA pin from tuner.
16.Power on/Check SCL voltage---ok.
17.Check SDA voltage to tuner PCB----ok.
18.Now SCL,SDA voltage---- ok.
19.Power off/measure ohms tuner SCL pin---high ohms.
20.Measure ohms SDA pin----low.
21.That means tuner SDA pin short.
22.Power on/Then-----

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