LG MICRO Hi-Fi SYSTEM Service Manual page 19

8. TOUCH-PAD PART CHECK
TOUCH-PAD CHECK
YES
IC305
28pin check 5V
YES
Check
IC305 13pin, 11pin,
IC100 96pin:CLK,
95pin:DATA
YES
OK
9. PWM MODULATION PART CHECK
PWM MODULATION
PART CHECK
YES
Check
P7905 9,10pin 3.3V
YES
Check IC604 PS9831 VDD
pin power (4,10,22,29,39,47,
56,65,72,87,94) check X601
2pin 3.3V
YES
Check if X701
12.288MHz is working
YES
NO
PN352 1pin 5V
YES
OK
NO
Check resistance output of
line CLK:R128 DATA:R126
YES
OK
NO
Refer to SMPS
troubleshooting
Check the
NO
related part of
X701
YES
OK
3-6
NO
Refer to SMPS
troubleshooting
NO
Replace the related part
NO
Replace the related part