Service manual

SERVICE MANUAL LS07 chassis
22
No answer,no key
press,no remote control
Is outside adapter(or inside)
output 12V normal?
Mend or change
adapter
NO
The connection of
Main board and key
press ,remote plane is
reliable or not?
YES
Reset the connect
lines
Is U13Ўў U22 output
port voltage normal?
NO
YES
Check U13Ўў U22
Outside circuit
NO YES
Check each supply power pins
voltage of U13Ўў U22 output to
U2 are reliable or not?
Change U2
1Ўў check outside parts of an
apparatus of supply power pin .
2Ўў check the jointing is OK or
not.
YES One pin has no voltage
2Have sound not picture, indicator light work normally
indicator light work,but black screen
when pressing down the power supply
key
Observe back lamp is on or off
NO
YES
U13Ўў U22 output voltage
is normal or not?
Check U13Ўў U22
Outside circuit
NO
YES
Check each supply power pin voltage
which output from U13Ўў U22 to U2 is
normal or not?
Change U2
1Ўў check supply power pin outside
parts of an apparatus
2Ўў check the jointing is OK or not
YES One pin no voltage
Cheeck inverter supply
power voltage and
connect line