Sony KD-49X7 D Series Service Manual page 113

4.4 NO PICTURE: TUNER
FOR 12V LNB Voltage Checking: @ AEP_W and JP_SKP
12V LNB Voltage Checking
Check fuse F2800
NG
Change the fuse
OK
Check LNB power line
+12V_MAIN at R495 = 12V?
N
G
AC adapter or G-board
G-board
Check harness between
B-Board and G-board
OK
Please refer G-board
troubleshooting
OK
Check P_ON_LNB signal line
at R446 = 3.3V?
N
G
AC adapter
Please refer DDCON
troubleshooting
N
Harness broken
G
113
MOSFET
OK
Q408/Q409
broken
113