Sony KD-49X9 F Series Service Manual page 52

4.4 NO PICTURE: @ TUNER
FOR 12V LNB Voltage Checking: @ AEP and J
+12V_LNB Voltage Checking
Check fuse F2801
NG
Change the fuse
P
OK
Check LNB power line
+12V_MAIN at R495 = 12V?
NG
Check +12V_Main at CN400
(JL401/JL411)
NG
Check harness between
B-Board and G-board
OK
Please refer G-board
troubleshooting
OK
Check P_ON_HL signal line
at CL414(R451) = 3.3V?
NG
OK Please confirm
Power Sequence u-
com
NG
Harness broken
OK MOSFET
Q408/Q409
broken
52