Troubleshooting - Daewoo DQD-2100D Service Manual

TROUBLESHOOTING

1. POWER circuit
Caution
You must use insulated trance during the first part test of POWER circuit.
D821, D822, D823, D824, D825,
+5V obtained at IC802 base and
+12V obtained at Q823 drain and +5V
+3.3V obtained at Q821, Q822 base when
Check Q823, Q824, Q821, Q822 and
No POWER
POWER cord/fuse is OK?
YES
Voltage connected at D801?
YES
Voltage connected at L804?
YES
Switching wave at T801 pin
#6,7,8?
YES
D826, D827 are OK?
YES
+2.5V obtained at emitter?
YES
obtained at Q824 drain?
POWER OFF "H"?
neighboring ITEM
NO
Exchange POWER code/fuse
NO
Check L801,L802
NO
Check Q801
NO
Check D803,D804,D805
NO
Exchange inferior ITEM
NO
Check IC801, IC802
NO
Check L812, L822
NO
Check DVD PCB
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