Samsung YP-Q1 Service Manual page 22

4-1-4 No LCD Backlight
Symptom LCD Backlight does not turn on
1 Check C312 on 3.4V
Major Checklist
2 Check CON802 LCD B-to-B connector
No LCD Backlight
Check Power is OK
Yes
Check C312 on 3.4V
1
Check CON802 LCD
2
B-to-B connector
No
Samsung Electronics
No
Yes
 Refer to wave pattern
image of Fig. 4-4.
Check No Power 4-1-1
Yes
Does the same
symptom persist even after
replacing the LCD?
Yes
Replace the BOARD
(needs thorough examination).
Troubleshooting
No
Replace LCD
4-9