Daewoo LM32L1 Series, Service Manual

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7. Trouble Diagnosis
7-1.Facts you must know when trouble Diagnosing or Repairing.
A.Trouble diagnosing and repairing of set mean find out which PCBs or blocks
are not working and replace them with new PCBs. Repairing the broken PCBs
are not necessary Keep the broken PCBs and return to service center or R&D
center.
B.This TROUBLE DIAGNOSIS list only contains representative and simple PCB
trouble diagnosis or to repair, contact R&D center.
C.Basic TROUBLE DIAGNOSIS process.
D.Required equipments for trouble diagnosis
-Digital Multimeter
User Mode : measure DC VOLTAGE, DIODE VOLTAGE, SHORT/OPEN TEST
-Screwdriver or electric screwdriver, plastic adjusting tool
-Oscilloscope(for detailed examination only)
E.Each BLOCK operations explained in this manual include oscilloscope
waveforms, but these are for reference only and utilizing them to repair PCBs
is not necessary.
F.Before replacing PCBs, you MUST turn off the AC switch.
G.After the set is repaired, leave BACK COVER open for followings. Run
HEATRUN for at least 30 minutes by displaying TEST PATTERN(Full White)
of SERVICE MODE(Refer to Service Manual, 5, Service Mode). Check the
screen conditions and basic functions.(Remote Controller operation etc.)
H.After BACK COVER is closed, redo HEATRUN for at least one hour with Full
White input using TEST PATTERN of SERVICE MODE.
Check the screen conditions and basic functions.
Note:HEATRUN is conducted for at least 30 minutes with input TEST PATTERN
FULL WHITE.
Check problem
Symptoms Open
BACK COVER
Trouble Diagnosis
& Replace broken
PCB
Adjust new PCB
module HEATRUN and
Full Function test
Repair Complete