Samsung MX-C730D, Service Manual

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Samsung Electronics 4-1
Troubleshooting
4. Troubleshooting
4-1 Checkpoints by Error Mode
4-1-1 No Power
Check MAIN PCB
CON3 Pin 1: 5.6V?
No Power
Check or replace SMPS.
Check or replace SMPS.
No
Check reset
circuit in MAIN PCB UX1, UX2
part ok?
Yes
Yes
Check or replace SMPS.
Check MAIN PCB
PCN3 Pin 1 ~ 4 : 5V,
Pin 6, 9 : 12V?
No
No No
Check VFD Voltage
in MAIN PCB PCN3
Pin 13 ~ 15?
Check signal and signal
pattern.
Check pattern or replace
MICOM IC.
Yes
Yes Yes
No
No
Check MAIN PCB UIC1
UD1, 2, 3 : 5V?
1
Check MAIN PCB UIC1
Pin 14, 40, 55, 89: 5V?

Refer to wave pattern
image of Fig. 4-1.