Service manual

Page 38
MODELS: LT-3280D/LT-3780D
2. No picture displayed and picture errors.2. No picture displayed and picture errors.
2. No picture displayed and picture errors.2. No picture displayed and picture errors.
2. No picture displayed and picture errors.
Note ) It applies when there is no screen display or an unusual screen is outputted, although
24V(Voltage between pin4(GND) and pin6(24V) of Connecter-PC) from PWB-POWER
is outputted normally and the back light is turned on.
*Input source changes in following order with DEVICE UP button of remote control or DEVICE
button of front switch.
PC Monitor Link
2-1. No picture displayed and picture errors of all input.2-1. No picture displayed and picture errors of all input.
2-1. No picture displayed and picture errors of all input.2-1. No picture displayed and picture errors of all input.
2-1. No picture displayed and picture errors of all input.
Is all harness connected correctly?
(especially between PWB-MAIN
and LCD PANEL (CNF1))
NO
Poor harness connection or
defective cable.
YES
Are the specified voltages available at the
connectors below?
NO
CN
Name
Pin No. Voltag
e
S5V PD 9 5Vdc
S3.3V PD 10,11 3.3Vdc
4.5V PD 12 4.5Vdc
Psave1* PE 2 3.3Vdc
Psave2* PE 3 3.3Vdc
Psave3* PE 4 3.3Vdc
* control si
g
nal of S3.3V
Problem is in the following
circuit (and peripheral
circuits) .
Voltage with
problem
PWB
including
the circuit
in problem
S5V
POWER
S3.3V POWER
4.5V
POWER
Psave1
MAIN
Psave2 MAIN
Psave3
MAIN
YES
Problem is in IC300 or IC400 or their
peripheral circuits.
Please exchange PWB-MAIN
*When it cannot still fix, it may have a problem with LCD-Module.*When it cannot still fix, it may have a problem with LCD-Module.
*When it cannot still fix, it may have a problem with LCD-Module.*When it cannot still fix, it may have a problem with LCD-Module.
*When it cannot still fix, it may have a problem with LCD-Module.