Power Supply On I/O Board - LG RHT497H Service Manual

2. POWER SUPPLY ON I/O BOARD

no Sw_12vG
yeS
is the
vcc (14v) supplied to
q164 collector?
yeS
is there
about 12.5v at
Zd151 & q164
base?
yeS
is the
vcc (33v) supplied
to q162 emiter?
yeS
is there
about 0v at
q162 base?
yeS
is there
about 5.3v at r170
and 0.7v at q165
base?
yeS
check q165 and replace
no
check d124 on SMPS
board and replace
no
check q164 and replace
no
check d126 on SMPS
board and replace
no
check q162 and replace
no
check power supply
Sw_5.3va on i/o board
3-4