B. Power error
No power
Standard Repair Process
Established
date
Revised date
2008. 3 .26
6/13
LCD TV
Error
symptom
Power LED
On?
Y
DC Power on
by pressing Power Key
N
Normal
operation?
Check Power
On ‘”High”
Check
Power LED
Replace
Power
Y
OK?
☞
A17
☞
A19
On?
N
y p
g
y
On Remote control
Y
operation?
On ‘”High”
Check Power cord
was inserted properly
Power LED
Power
B/D
Replace Main B/D
☞
A20
. Stand-By: Red
. Operating: Blue
Measure voltage of each output of Power B/D
☞
A20
Check & Repair
Mechanical Power switch
on Local control of TV
※
☞
A21
N
Y
Normal
voltage?
Replace Main B/D
N
Normal?
Check ST-BY 5V
Replace Power B/D
Y
Normal
voltage?
Y
☞
A18
Y
Replace Power B/D
N
Replace Power
B/D
Close
B/D
※
’09 years new model apply
mechanical power switch
to reduce power consumption in stand-by status.
If mechanical power switch off
If mechanical power switch off
→
Doesn’t turn on by remote control
→
Doesn’t appear LED light
Please refer to the A21 Page
6
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Only for training and service purposes
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Summary of Contents for 42SL90QD
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