LG L1404R Service Manual - Page 29

ElectrIc Parts

Page 29 highlights

ElectrIc Parts Troubleshooting Guide Possible Trouble 1 The unit does not operate. Is the Trans input power AC 115V? NO (208/230V for LWL1230WAL) ••CChheecckktthheeFFuussee.. ••CChheecckkththeewwiriirninggddiaiaggraramm. . YES Is the Trans output power NO about AC 14V? YES Is the Trans. output shorted? NO • Check the AC PCB pattern. YES • Replace the Trans. Is output Voltage of IC01D NO DC 12V? YES • Replace D02D~D05D. • Replace IC01D. Is output Voltage of IC02D NO DC 5V? YES • Replace IC02D. Is the reset circuit OK? NO (The No.14 of Micom is 5V.) YES Is the connection between NO AC and DC OK? YES • Replace IC01A, C01A. • Connect connector exactly. NO Is the voltage No.40 of Micom DC 5V? YES Replace AC PCB Ass'y. • Check the PCB pattern. Service Manual 29

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Service Manual
29
Troubleshooting Guide
Is the
Trans input power AC 115V?
(208/230V for LWL1230WAL)
Is the Trans output power
about AC 14V?
Is the Trans. output shorted?
Is output Voltage of IC01D
DC 12V?
Is output Voltage of IC02D
DC 5V?
Is the voltage No.40 of Micom
DC 5V?
Replace AC PCB Ass'y.
Is the
connection between
AC and DC
OK?
Is the reset circuit OK?
(The No.14 of
Micom is 5V.)
• Check the Fuse.
• Check the wiring diagram.
• Check the AC
PCB pattern.
• Replace the Trans.
Replace
D02D~D05D.
• Replace IC01D.
• Replace IC02D.
Replace
IC01A, C01A.
• Connect connector
exactly.
• Check the PCB
pattern.
NO
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
NO
YES
Possible Trouble 1
The unit does not operate.
ElectrIc Parts