Samsung HW-C450, Service Manual

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Samsung Electronics 4-1
Troubleshooting
4. Troubleshooting
4-1 Checkpoints by Error Mode
Oscilloscope Setting Values
Voltage/DIV 1V/div
TIME/DIV 500ms/div
4-1-1 No Power
Yes
2
Check if 5.6V is
measured at the LA1 of the Power
PCB(SMPS).
Check SMPS, MAIN PCB
SMPS: CN2 No. 1 (5.6V)
MAIN: PCON1 No. 19 (5.6V)
Check the power circuit of
SMPS PCB
(Check the outputs of TRANS)
No
Yes
No
The power does not turn on.
AC Cable check and replace
Yes
Yes
Check if “H(3.3V)” is
measured at the pin 26 of the
UIC1 when Main PCB
power is turned on.
Replace the Micom (UIC1).
Replace the connector CN2.
No
Check the
power(3V) at MAIN PCB
P_CON1 NO.18

Refer to wave pattern
image of Fig. 4-1.

Refer to wave pattern
image of Fig. 4-2.
1
Is there 5V on the UIC1 Main PCB
pins #6,7,41, and 42?
Check the power(3V)
SMPS PCB CN2 NO.2
No
No
Replace the SMPS.
No No