XOCECO LC-27W18S, Руководство по обслуживанию

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26
Yes No
No Yes
NOTE:
When pin 10 of N301 is low level, remove V301 and then check the correspondent pins of
N301are high level or not, the reset circuit fails to work properly if it is high level. If pin 42 of N301 has
no square-wave, remove R365, if the square-wave appears, then it is probably the FLASH of N302 fails
to work properly. When it comes to check the periphery circuit of N301, N302 and N303, use
oscilloscope to check the connecting resistor’s pin among N301, N302and N303 besides checking the
connection of correspondent components, if regular square-wave or no signal is found, then it represents
that one of N301, N302 or N303 fails to work properly, probably is N302. If R110 and R111connects
N301 with N101fails to work will also lead to the failure phenomenon.
( 2) No picture but with sound( blue screen and OSD appear)
Yes No
Yes No
NOTE: Please refer to checking procedure (5) to get the methods for checking the phenomenon of no picture but
with sound of HDMI channel
Check N301 and its reset circuit
，
especially
check the critical components namely
V301and D302
Check if pin 42 of
N301is square-wave
Check N301 and its crystal
oscillation
Check the periphery circuit of
N301,N3022 and N303
No picture but with sound
Whether backlight lights up.
Check if other channels have no
picture
Check N101 and
its periphery
Refer to (4) checking
procedure
Check backlight board, CPU
pin 77 backlight control
condition.