Samsung LE46C530

[nezocas]

Hi,

This tv as got image and sound, but no back ligth.
Power supply BN44-00341B

Resistors 802/805/807/810 all 1M5 allready replaced
C1818 0.47uf measured OK
Fuse FS802s in the middle of the board OK
By disconnecting the main board, and if I power up the power supply, the back ligth comes rigth ON
PFC is LOW only 310v on both filter caps.
ESR and capacitance on all cap´s were tested

Need some help
Regards

[nomoresonys]

Re: Samsung LE46C530

Check all the diodes if you haven't already.

[nomoresonys]

Re: Samsung LE46C530

Is the service manual in here?

[budm]

Re: Samsung LE46C530

Is your AC 230VAC, if it is then at standby the DCV on the main cap should be about 230VAC x 1.414 = 325VDC, you indicate only 310Vdc so you need to verify.

[nezocas]

Re: Samsung LE46C530

Is your AC 230VAC, if it is then at standby the DCV on the main cap should be about 230VAC x 1.414 = 325VDC, you indicate only 310Vdc so you need to verify.

Yes my AC is 230v

As you guys asked, when I was checking all diodes, found DP807 (next to FAN ic) shorted in circuit, dessoldered it and it was good outside, next dessoldered CP810 it was good also....I thinked to my self, this "short" is caused by a parallel low value resistor.

Let´s check the standby voltage at main cap as you guy´s asked.

To my surprise the backligth came ON.

I only think one cause to this, the glue under one of those components, causing parasitic readings and forcing the backligth to go OFF.

Set will be under test the next 2 days....will report back.

PS: now voltage at main cap raised from 310v to 385v

Best regards
Nezocas

[nezocas]

Re: Samsung LE46C530

Hi,

Set repaired

Thank´s