Philips DVP3680KX Service Manual page 19

Remote reception is insensitive or fails.
Remote reception is
insensitive or fails.
Go
Check if the remote
control works properly.
Yes
Check if the power supply
voltage to the remote censor
is normal
Yes
Use an oscilloscope to check if there is
output waveform from the first pin IR of the
remote censor after pressing button on the
remote control.
Yes
Check if there is IR
signal on pin 16 of U1
No
Correct connection
4-9
No
Check battery
No
Check R96、C93
No
REM301(PIN1 - RC waveform)
Yes
Change U1
IR waveform
Trouble shooting chart
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