Toshiba BDX2500KU Service Manual page 50

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
of IC4201,C4205,C4206 and R4206
are normal (at a high level for tens of
milliseconds, then constantly at 3.3V)
Yes
Check whether there is
27MHz signal output.
Yes
Check if there is 600MHz
signal output on R5201.
Yes
Check if short-circuit and bad
solder exist on IC4001.
Yes
Reconnect the component
or replace Main PCB.
11-10
No
Check the loaded circuit.
No
Change
and R4206 or replace Main PCB.
Crystal oscillator X4201
No
and peripheral components
are defected or eroded.
or replace Main PCB.
No
IC4001 Pin K7,J7 PCLK waveform
No
Check IC4001 or replace Main PCB.
Trouble shooting chart
CVBS (R1 point) waveform
IC4201,C4205,C4206
27MHz waveform
Check whether
short-circuit or bad solder
on IC5201,IC5202,IC5203.
No
Yes