Samsung MM-26 - Troubleshooting; Main

6. Troubleshooting
6-1 Main
6-1-1 Power Malfunction
Samsung Electronics 6-1
Front PCB µ-com VDD(5V)
normal?
UIC1 pin no. 9,36,37
Replace RIC1
Main PCB RIC1(BA3950) IN: 20V
Input voltage normal?
Yes
Check the Power PCB;
RF4 (T3.15 AL 250V)
Yes
Front PCB
Does UX1(4.5MHz)
oscillate ?
FRONT PCB POSNS
voltage normal ?
(pin no. 13 ;5.0V)
Check the Main PCB
RZD2,RC4,RR3,RR4,
RR2,RC1,RD1
Replace µ-com
Yes
Yes
Front PCB
When the power is
ON 'H' displays
at pin no. 49 ?(5V)
Yes
Connect Front PCB and Main PCB.
Check the connector Main PCB.
Wafer JWC3,JWC4
No
No
No
No
No