DVD player Troubleshooting( what should be my next step)

[lightray03]

hello im a newbie troubleshooter for electronics, and an ECE student,
we have a dvd player in house, and when my parents tell me that our player is turning on its on/off state,i try to repair it
at first i discharged the filter capacitor and replace it with a new one,and test it actual but i forgot something the output of the powersupply

it has wrong inputs to the board next to it, pls refer below (sorry if i have no screenshots/picture)

+5v       gnd     +12v   -12v (INPUT supply to the board
-12v    +12v   +5v       +5v  (Output from the power supply)

before that i noticed the FR diodes are broken and emits a smoke, i replace all the FR diodes,
but still nothing, it has supply, but what makes me think is that rather than 5v and 12v it outputs 15 and 20v
but when i tip the probe to the board and the power supply, it output 5v and 20v
when i tried to replace 431 transistor still nothing happens it does have supply but does not turning on,
(sorry for my bad english) please help me in what to do next

[amyk]

Pictures? Schematic (you'll have to trace one if you can't find one)?

Or are you saying that it was fried because of wrong input voltages? In that case it's probably beyond repair.

[SeanB]

You put the cable in the wrong way round, and likely this has burnt out the diodes, and the main board as well.

[lightray03]

You put the cable in the wrong way round, and likely this has burnt out the diodes, and the main board as well.

i've checked all the diodes on the main board and the transistors as well, and they are all good, i've fixed the supply and
supplied the board with the correct voltage,

now the problem is, it plays and turn ON but when the movie plays or the inserted disk plays, it suddenly pause and leave the LED display on but having no power on the DVD/CD Driver