Toshiba 42HL67 - 42" LCD TV, Руководство по обслуживанию

Страница: 15 / 32

Does the back light
function and then turn
off?
YES NO
Is
the back light
supply source present
shortly after the power
switch is pressed?
(24V-Pins 1-5
CN804)
YES
NO
Suspect the
back light
supply source.
Is the back
light switching
signal (3VDC Pin 1-
CN61) present shortly
after the power switch
is pressed?
YES
Suspect
System
Control or
Low-B supply
problems.
NO
If it is available , try the
CCFL inverter. If this does
not help, replace the LCD
display. ***
*** Warranty Concession
required for LCD panel
replacement. Digital photo
may be requested.
Contact Technical
Support.
Does
the screen light
unevenly? (Normal
screen with a shaded
area)
NO
This
normally
indicates a
defective CCFL
(Lamp). The
display should
be replaced.
***
Using
a scope or frequency
counter, is the CCFL
inverter operating?
Suspect the
CCFL inverter.
NO
YES
Operation of the inverter can
be determined by placing a
scope probe or frequency
counter test lead NEAR the
inverter. If the inverter is
operating, the operating
frequency (40 to 70 Khz) or
waveform pictured below will
be displayed.
Do not connect the
test leads directly to
the inverter!
YES
14
14