26. Selftest
check pin26
1.no H/V sync & IF cable pin5 floating
- show msg.
2.H/V sync exist & IF cable pin5 to ground
- normal
3.H/V sync non-exist & IF cable pin5 to gnd
- power saving
check idle status
Sda=pin9=hi
Scl=pin8=hi
8,9. DDC bus
check idle status
Sda=pin22=hi
Scl=pin23=hi
22,23. IIC bus
check key
+,-,H-Shift,H-Size,V-Shift,V-Size keys
19. Keypad
Check
3838~3844
15,16. EEPROM
write protection
check
pin15
pin16
write :
low
hi
read :
don't care
normal :
hi
low
check
7806 24W04
7501 TDA4857
7099 TDA4886
check
from 5V to 0V
3. Reset
check
7808/6813/3812
check
Active=low
no active=hi
24. Degauss
Repair Flow Chart
44
104S CM23 GSIII