Sharp LC-20C2E, Service Manual, Page: 13 / 50

13
LC-20C2E
TROUBLE SHOOTING TABLE
(Continued)
No picture
Check all the settings microprocessor's adjust process menu.
Is in/output of IC801 normal?
Is in/output of IC1201 normal?
Check IC801 and its peripheral parts.
Check IC1201 and its peripheral parts.
Check IC402 and its peripheral parts. Check IC801, AV1 line and its peripheral parts.
Check LCD panel voltages and waveform.
Yes Yes
No No
No picture at all
Is in/output of IC402 normal?
Is input at pin 73 of IC801 normal?
Yes
No No
No TV and VIDEO 1 output
Is voltages at pin 3 of W7 and pins 3, 4, 5 of W14 tuner normal? Is output at pin 2 of W7 tuner normal?
Check the power line.
Check tuner and its peripheral parts.
Is input at pin 3 of IC402 normal?
Is the pins 2 and 4 of IC402 at "H" and "L" state?
Yes Yes
No No No No No
Yes
No TV output Is the pins 65 and 66 of IC2001 at "H" and "L" state?
Yes
Check the its line. Check the its line.
Check IC402 and its peripheral parts.
Is input at pin 1 of IC402 normal?
Is the pins 2 and 4 of IC402 at "L" state?
Check the its line. Check the its line.
Check IC402 and its peripheral parts.
Is the pins 65 and 66 of IC2001 at "L" state?
Yes Yes
No No No
No VIDEO 1 output