Daewoo DV-T5T2, Service Manual

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1
TROUBLESHOOTING GUIDES
1. POWER CIRCUIT
When changing the parts which are broken first, remove the power plug from the socket and then discharge the voltage
across the terminals of C805. (Use an external K
Ω
resistance)
When check the primary circuit , use the oscilloscope isolated properly (Use the isolated transformer) and connect
GND to the primary GND, however it is not necessary to isolate the oscilloscope when check the secondary circuit.
A. CHECKING THE PRIMARY CIRCUIT.
No output Voltage.
NO
NO
NO
YES
Prepare the oscilloscope
connected the isolated
transformer
Check L801
Check R802, D801
YES
YES
YES
YES
YES
YES
YES
YES
Check R804, R803,R809,R807
C805,C807,D802
Check F801 Fuse.
Is voltage applied to D801?
Is voltage applied to the
terminals of C806?
Is voltage applied to
Q801 S?
Is voltage output from pin 3
of IC801?
Check Q802, Q803, Q804,
Q803, C809, C811
Check the Secondary circuit
Check D811
*D802:Protector Diode
* Protector Diode
Appendix