Daewoo DLA-32C7LAB, Service Manual

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7. Hardware Troubleshooting : SMPS
1) FEL-3237UL : DLA-32/37C7LABD
'CHECKING FLOW ABOUT INFERIOR SMPS' (MODEL NAME : FEL-3237UL)
PAGE : 1/2
1. Stand-by 5V is working out.
A. Can you check In-put voltage(DC) of the capacitor(Location No. : C22)?
2. MAIN Out-put voltage is working out but Stand-by 5V is working.
A. Is Power On signal(3.3V) supplied to Base of Q7?
YES
YES 1.1 Checking open and short of Out-put side wire cable.
NO
1.2. Checking open and short of the around parts that was connected IC1(STR-A6252).
(Location No. :R12,ZD1,D5,D7)
1.3. Checking open and short of IC1's each pins.
1.4 Checking open and short of D15 each pins.
NO
1.5. Can you check the Fuse(F1) condition(open and short)?
YES : Checking 1.2 item after changing FUSE. NO : Checking 1.5 item.
1.6. Checking open and short of BD.
YES : Changing BD.
NO : Checking open and short of Z1, LF1, LF2.
A. Can you check that Vcc voltage of IC1 was supplied from DC15V to DC27V?
YES
NO
2.1. Can you check the Q2's condition(open and short)?
YES : Changing Q2. NO : Checking 2.2 item.
2.2. Can you check the ZD7's condition(open and short)?
YES : Checking ZD7. NO : Checking 2.4~2.5 item.
YES 2.3. changing Q7.
NO
B. Can you check the Q7's condition(open and short)?
C. Can you check that Vcc voltage of IC2's No.8pin was supplied from DC10V to DC18V?
NO
2.4. Checking open and short of the around parts that was connected IC2(L6565).
(Location No. :ZD4,ZD6,D3,D4,R50,R8D1,D2)
2.5. Checking open and short of IC1's each pins.
YES 2.6. Checking open and short of MAIN BOARD.
2.7. Checking open and short of MAIN BOARD.