Daewoo DX-N111N, Service Manual

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15
TROUBLESHOOTING
14
TROUBLESHOOTING
No output 12V of IC 801
Check the 5V at pin 4 IC804.
Vout =IC804 out voltage.
Is the Q801 turn on?
Check the pin1 in IC806
5V <Vin
Replace the IC804
Check the IC806
Check the previous
Power circuit
Replace the IC804
NO
YES
YES
YES
NO
Check the R828,R829,D805
NO
NO
Check the 18-21 pin IC801
Vdd =Vin
Check the pin 11-14 in IC 804
42V Oscillation.
Under the 17V
YES
Check the 5V at pin 4 IC804.
Ever 12V =IC804 out voltage.
Check the D862,L811,IC802
YES
YES
YES
YES
NO
NO
Over the 17V
Check the Q801
Check the D804
No output 6V of IC 802
Check the pin 11-14 in IC 802
42V Oscillation.
Check the pin 25 in IC 802
25V Oscillation.
Check the pin 8 in IC 802
10V Oscillation.The same frequency
Of Pin25 in IC802.
Check the D862,L811,IC802
Check the D861,IC802
NO
Check the previous
Power circuit
NO
YES
YES
YES
Check the D861 IC802
NO
NO
Check the 18-21 pin IC802
Vdd =Vin