LG TL-AT130M Service Manual page 13

SECTION3 ELECTRICAL
ELECTRICAL TROUBLESHOOTING GUIDE
(4) No 5.2 A (TO AVCP , BIAS)
No 5.2V
Is D106 normal?
YES
Is Q153 normal?
YES
Is there voltage (about 0V)
at Q157 collector.
YES
Check/
Replace Q156
NO
Replace D106.
NO
Replace Q153.
NO
Replace Q157.
(5) No 10V
No 10V
Is D109 normal?
YES
Is Q170 normal?, Is there about
13.5V at Q107 Base?
YES
Check/ Replace
D155, D156, D157/\.
3-3
NO
Replace D109
NO
Check/ Replace
Q107, ZD103