PHILIPS DVD728/021
Service Manual

EN 24
5.3.4

5.

DVD728-731 /0X1

Service Hints, Trouble Shooting and Fault Finding

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B When read disc, Laser ON OK? Signal LDO1 and LDO2  is normal? Y Y Voltage of TP22 &TP24 OK? N Check the peripheral circuit of two transistor (item 7620 & 7621) Check the peripheral circuit of MT1366 Check the peripheral circuit of two transistor (item 7620 & 7621)

N

N

Load a disc?

N

Laser off Y

Check the circuit to connect LOADER OPU maybe damaged

Y

Focus On ok?

N

Any signal on pins A B C D E F of MT1366 Y Signal FEO (pin18 of MT1336) correct?

N

Check the circuit between Loader and MT1336

N

Check the peripheral circuit of MT1336

Y

Y Check the circuit from Pin18 of MT1336 to Pin205 of MT1379

Disc ID correct?

N

Signal of Pin 19 (RFL) of MT1336 normal? Y Check the circuit from Pin19 of MT1336 to Pin206 of MT1379

N

Check the peripheral circuit of MT1336 and itself.

Y

Spindle on OK?

N

DMSO (pin18 of MT1379) normal? Y Signal SP+  &  SPcorrect?

N

Check MT1379 and its peripheral circuit.

N

Check BA5945 (motor driver) and its peripheral circuit

C

Y Check the connection between spindle driver and BA5945

CL 36532024_008.eps 210303

Figure 5-4 No Sound