Toshiba BDX2500KU Service Manual page 45

All output voltages on the Power board is 0V or deviated.
All output voltages on
the Power board is 0V
or deviated.
Yes
Check whether FU1 is blown.
Check whether there is
130V on C8.
Check whether there is
feedback signal on pin2 of U1.
Yes
Check if +5V,+12V are short.
Check whether the components in the
short-circuit voltage are defected or eroded.
Yes
Yes
Yes
11-5
No
Replace FU1 or replace Power PCB.
No
Replace C8 if D17, D19, D20,D21 are
normal or replace Power PCB.
No
Check/Replace U1 or replace Power PCB.
U1 (PIN3 - FB waveform)
No
Check whether U1 are eroded.
Trouble shooting chart
U1 (PIN6-Drain waveform)