Philips DVP3855, DVP3879, DVP3893, DVP3896, DVP3898, DVP3800 service manual No video picture, no sound

4-10 Trouble shooting chart

No video picture, no sound.

No video picture,

no sound.

Check whether all the voltages from the power board to the decoder board are normal.

Yes

Check if the reset circuit consisting ofCE1,Q1,Q2 is normal (at a low level for tens of milliseconds, then constantly at 3.3V).

Yes

No

No

Check the loaded circuit

Change CE1,Q1,Q2.

CVBS(R884 point) waveform

27Mhz waveform

Check whether there is 27MHz signal output.

Yes

No	Crystal oscillator Y1 and
	peripheral components
	are defected or eroded.

Check if there is 135MHz signal output on R193.

No

Check whether short-circuit or bad solder on U176,U186

Yes

SDRAM(R193 DCLK) waveform No

Check if short-circuit and
bad solder exist on Pin
72	No

Yes

Reconnect the component in

Check U1.

Yes