TH-P42C10 8 blinks

[Neelix]

Got this TH-P42C10 and it's giving 8 blinks(SS board SOS)

Number for SC board is TNPA4773 and although the SOS blinks indicate SS board, I figured it would not hurt to measure the voltages anyway. Ve, Vset, Vad and Vscn all measure within spec and remain stable. Vsus though starts at 187.7V and then drops to about 162V before the TV switches off

Number for SS board is TNPA4774. Ve measures within spec and remains stable. Vsus behaves the same as on the SC board, but that's to be expected. MID voltage which is fed back to the SC board, starts at 15.2V and then drops slightly to 14.8V before TV switches off. +15V(P) starts at 15.5V and then takes a sharp nose dive which is a clue

All the components on the SS board look fine under magnification. None of the transistors and diodes measure short. Looking at the diagram, the +15(P) is used to drive the Vsus Gen circuit that generates the sustain voltage. While still soldered onto the board, I measured all the components in the Vsus Gen circuit and as far as I can tell they all measure ok. I was wondering if anybody maybe came across a fault like this before or have any ideas?

[Neelix]

Re: Panasonic TH-P42C10 8 blinks

Also on the SS board I disconnected the cables going to the SS3 and SS11 connectors and the TV switches on then, but there's no picture which is to be expected. Vsus remains stable and does not drop

[Moreno83]

Re: TH-P42C10 8 blinks

Are you sure you dont have a short on the SC board? I would not be suprised if the tv misdiagnosis the fault.

For example , i got a 2010 model that gives me 1 blink error but has a shorted SC board.

[Hombre]

Re: TH-P42C10 8 blinks

I don't think that he have short on SC because tv stays on with SS isolated, otherwise it would trip probably SOS6 or 7.

Can you measure VSUS while tv is on, to see what voltage you have going out from PSU?

[martino]

Re: TH-P42C10 8 blinks

I would try the test patterns first.

[Hombre]

Re: TH-P42C10 8 blinks

If you mean on test patterns performed by/with a-board i think it would not be possible to do it, without SS board.

Maybe some of transistors are damaged, but not complete short like 0 ohm, it happened few times that resistance is like 300 ohm and if you are measuring with diode mode on multimeter it can fool you. Q101, Q102 maybe, i don't know, just shooting blinds.

[Moreno83]

Re: TH-P42C10 8 blinks

you are right Hombre , didnt read the thread correctly.

[Neelix]

Re: TH-P42C10 8 blinks

Thanks everyone for you replies. I'm going to order the driver IC, transistors and diodes for that part of the circuit and hopefully the fault will be fixed