Panasonic Viera tv P46st30 no standby light

[tvtimmy]

Re: Panasonic Viera tv P46st30 no standby light

I would start with finding all the shorted parts on the SN board. That is where your problem is. Check the parts marked with a Q for a short. You will find 4 to 6 of them to be bad. Tbe SN board is the one with the orange ribbons.

[waakye]

Re: Panasonic Viera tv P46st30 no standby light

Will do that and report back bout my findings

[Robinsosa]

Re: Panasonic Viera tv P46st30 no standby light

Check this training manual.

[waakye]

Re: Panasonic Viera tv P46st30 no standby light

@ tvtimmy, I found a lot of mosfets on the SN board that were shorted. I will order the parts. It seems that I can not find the 30F131 from Digikey. Any alternative? Thanks again

Thanks Robinsosa. It was very informative.

[tvtimmy]

Re: Panasonic Viera tv P46st30 no standby light

I bought 100 of them from Utsource in 2019. There are a LOT of fake parts out there, like on ebay. These were all good. They were 47 cents apiece.

[waakye]

Re: Panasonic Viera tv P46st30 no standby light

Thanks tvtimmy. I will order from Utsource

[tvtimmy]

Re: Panasonic Viera tv P46st30 no standby light

Test them before you install them!

[waakye]

Re: Panasonic Viera tv P46st30 no standby light

Change the shorted mosfets on the SN board and plug it in and am still seeing no standby led. The TV is still not turning on. Any idea on where to check?

[tvtimmy]

Re: Panasonic Viera tv P46st30 no standby light

Show us pictures of your work. Check the mosfets(lbgt's) again for short.

[waakye]

Re: Panasonic Viera tv P46st30 no standby light

Hi tvtimmy, thanks for the reply. I measured the mosfets and there are no shorts. I have attached pictures of my work. Shouldn't the standby led at the set be on even if there are short on the SN board?
Thanks again.

[tvtimmy]

Re: Panasonic Viera tv P46st30 no standby light

Check the dg302 fets on the board as well as q600 in diode mode. Try unplugging everything from the sn board and plugging in the tv to check for a stand-by light.

[waakye]

Re: Panasonic Viera tv P46st30 no standby light

I unplug the SN board and still no standby led. The dg302 and Q600 are not reading any shorts. On the SN board I don't read any shorts.
Thanks

[tvtimmy]

Re: Panasonic Viera tv P46st30 no standby light

You have to check them in diode mode, not in continuity. You may have a bad mainboard.

[waakye]

Re: Panasonic Viera tv P46st30 no standby light

Ok. I will check in diode mode. I also bought a new motherboard and same issue with no standby light on. Will I get a voltage on pin P2 and P11 on the power supply board when AC power is applied?