Shivaki STV-32LED11A, Service Manual

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because the failure in power on can lead to a no-display problem.
No display (including white screen, black screen, etc.)
Note: If the troubleshooting given below can not help you, change the LCD panel for a try. But we strongly suggest
you
regard changing the panel as the last step of fixing the display problem.
If it is proved to have been electrified and turn on, check the LVDS cable first.
Check if both of the two plugs of the flat cable between mainboard and power board have been well inserted into
the slots.
Unstable power supply can also cause serious display problem.
If the display problem only happens in one input mode, that may be caused by wrong version software. Update the
new
software. If that can
’
t help, change the main board for a try.
Bad LVDS cable and inappropriate panel driving voltage is still the biggest factor of this problem. So check them
first.
Screen tearing, or there exists moire on screen
If the cable and voltage are correct, update the software for a try.Sometimes the fastening pieces can make
unproper pressure to LCD panel, check them out.Refer to chapter 5 for more details and resolution ways.Refer to
chapter 5 for more details and resolution ways.If the screen tearing happens in one or several input sources while
the other source can display normally, it can be caused by bad mainboard most likely. Please change the
mainboard for a try.If the bad line is very narrow, it is usually caused by LCD panel malfunction, change the panel
for a try.
Straight dark/light line(s) on screen
If the lines link together and become a bad band, upgrade the software and then check the ports abd circuits of
brokendownoutput mode(s).If the dark/light line ,or band, apprears in all the input modes, please change the LCD
panel. But we suggest you check the panel inlet board(which links the panel and mainboard though LVDS cable)
first, because sometimes the liquid crystal displaying unit is okay, while the inlet board has a transmitting problem,
which also will lead to a displaying failure. If the cast or interference happens in only one input mode, check the
output port(on mainboard) and transmitting network (arround mainboard) of that mode.
Color cast or interference
If the cast or interference happens in all the input modes, please exclude the malfunction according to easy
troubleshooting for No Display. If that can not help, refer to chapter 5 for more details and resolution ways. In
addtion, most of this kind of problems come from the bad mainboards.
Chapter 4 Easy Troubleshooting
7.3 Troubleshooting for Audio
Check whether the speakers are broken first.
No Sound
Note: Comparing with the display problem, the audio malfunctions are easier to work out. Constantly, if you have
excluded
the possibility of bad speakers and bad connection of audio output, the problem generally comes from the audio
processing parts of mainboard. Please change mainboard for a try, or refer to chapter 5 for further information
about repairing. Check the wire that links the mainboard and speakers. Watch if there is fracture or cladding
material breakage.
Check the joint of speakers and audio wire, watch if there is poor soldering or fake solder. Besides, the polarity
mistake