samsung ps42a457

[call me al]

Hi all Have this samsung ps42a457 power supply clicking, customer said that the screen would come on but when signal was connected it would go off .have changed the logic board but still the same Any ideas much appreciated

[downunder]

Hi Al,

You may have low Vs volts, which collapse when signal is applied. Generally though, if the SMPS relay clicks on/off continuously due to protection, the fault is on another board. In turn, try disconnecting Y-Main, X-main, Control Board and see if clicking stops. Isolate the PSU and force it on via PS-ON and VS-ON, see if it stops clicking. Main board can also cause this, as I recently found out after ordering a PSU and ending up in the same position.

Bruce

[call me al]

Thanks for reply Bruce Have forced psu on voltages look ok clicking stops only when main board is disconnected Tryed it with psu forced on and all boards connected stays on but no picture Am thinking its main board trouble

[t1412]

i've had the same fault on the 43inch versions, and it turned out to be the xmainboard  you can get the board from emos thanks

regards
shaun   

[downunder]

Definitely sounds like the main board, Al.

Bruce

[t1412]

hi bruce i'm just going on the clicking fault, so you may be right cheers.