Philips 715G6353-P01-001-002H Low voltage from PSU board

[stomanata]

Hi,
I have 715G6353-P01-001-002H from Philips TV.
TV doesn`t start up even there is no red led light.
I noticed that 12V rail has 8.5V.
Suggestions for repair?

[William1967]

Re: Philips 715G6353-P01-001-002H Low voltage from PSU board

Is the stand by voltage present?
The 715G number is for PCB's without parts, do you have the modelnumber and the PLTV number on the white label of the power supply?

[lotas]

Re: Philips 715G6353-P01-001-002H Low voltage from PSU board

Hi,
I have 715G6353-P01-001-002H from Philips TV.
TV doesn`t start up even there is no red led light.
I noticed that 12V rail has 8.5V.
Suggestions for repair?

Check if your PFC is working, there should be about 400v DC on a large capacitor (C9814, C9815) in the hot circuit.

[stomanata]

Re: Philips 715G6353-P01-001-002H Low voltage from PSU board

Is the stand by voltage present?
The 715G number is for PCB's without parts, do you have the modelnumber and the PLTV number on the white label of the power supply?

715G6353-P01-001-002H is the whole number and there is the same board for sell and
also service manual of it.
There is pin #3 labeled PS_on and there is no voltage over it.
Over both capacitors (they are in paralel) there is 310V
Is there wiring but with control point/voltages on it?

[stomanata]

Re: Philips 715G6353-P01-001-002H Low voltage from PSU board

Check if your PFC is working, there should be about 400v DC on a large capacitor (C9814, C9815) in the hot circuit.

It is 310V DC. BTW can i add bridge over choke to ignore PFC?
It also mean to remove mosfer or PFC chip/controller

[stomanata]

Re: Philips 715G6353-P01-001-002H Low voltage from PSU board

If i`m not wrong, then if i apply +12v on PS_on, then it will start optocoupler IC9401 and this
will generate 12v on VCC_ON. But i can`t see VCC_ON on PCB. May be this is ON/OFF pin?