Ultrastudio 4k 2 Power problem

[NConstantinou]

i have the above device which consist of power supply and control board.
the power supply has output 12vdc which is connect to main board.as it is connected i get only 2.2vdc. when is unplugged i get 12vdc. is that correct. i do not have thunderbolt to test the device.

thanks

[CapLeaker]

Can be 2 problems:
A: The capacitors in the power supply are bad and can't handle the load
B: there is something bad inside the mixer and drawing a lot more current than it should.

Always go for the low hanging fruit first. Check, repair or replace the power supply first.

[R_J]

Try connecting the power supply 12v output to an automotive lamp like a 1157 or similar and see if it lights and check the voltage across it.

[NConstantinou]

thank you for your reply

i connected i 12v dc motor and i do get 12.6v across it. that means power supply is ok.
when i connect the 12v dc power supply to the connector (power supply+ control board) i do get short but mo matter what voltage i select the amperage does not pass 1.25-1.3a and components do not get hot to see what is defective.

Thanks

[CapLeaker]

Upload some high resolution, straight shot pictures using the attachment function, so we can see something.

[NConstantinou]

thanks for your reply.

i am attaching the images

[NConstantinou]

i managed to repaired it. there were 2 50mf 50v capacitor on main board and one of them was bad. i changed both.
i found that when i noticed that the feedback voltage on optocoupler was very low.

thanks for the help