SHARP LC23K7
Instrukcja Serwisowa

2. raster, but no picture

Check if the unit can operation?

yes

Check if the all channels have signal?

no

no no

Enter

factory-menu, CLEAR then turn

Replacing CPU board

operation EEPROM,

Which is no VGA/DVI signal of channels YPRPB TV Testing power supply (+5V-V) of video processing board no

Replacing CPU board

off , turn on again , it if display picture. yes Adjust CPU board again

Check input 24V of sound conversion board no Check input 24V-A of CPU board

Replacing U30

no

Testing PIN65 of U30 SYNC signal

yes

Display �NO-SIGNAL� no

yes

no Check output 24V-A of power supply board

Replacing U13

no

Testing 1VPP signal of TP1, TP2, TP3.

yes Replacing CPU board

Check if PIN2 1VPP signal and noise wave of P32? yes Check if PIN56 15.734KHz sync signal of U29? no Replacing U29

no

Replacing TUNER202

yes

2