Akai LTA-26C904, Service Manual

Page: 38 / 50

37
Chapter 4 Familiar Problem and Processing
1
．
Failure phenomenon
：
The picture is normal
，
but OSD has line in it.
The reason and the processing ： Check the pin of U2 and pin 80-160 of U1 for pseudo
soldering, and have pseudo soldering touched up.
2
．
Failure phenomenon
：
There is sound but no picture; there is no OSD when start up; and
the back light is bright.
The reason and the processing
： Check the connecting line to screen, and have it
connected well.
3
．
Failure phenomenon
：
There are no picture, no sound, and no snow flower dot in TV
mode, but AV is normal.
The reason and the processing
： Check the tuner and its peripheral circuits (including bus
and power supply). If the peripheral circuits work well but there is no output from tuner,
then the tuner must be failure.
4
．
Failure phenomenon
：
LCD television cannot be controlled(including no starting up with
red light on, remote control and local key having no effect, etc).
The reason and the processing
：
LCD television has crash phenomenon, restart after
power off.
5
．
Failure phenomenon
：
+5V_SB voltage has output, but there are no picture, no sound,
and back light and indicating light are not on.
The reason and the processing
：
Check other groups of voltage; if they have no outputs,
then check Flash to find if it is installed well or damaged; if Flash is OK, find out that if the
power supply and output voltage of U4 works well.