Panasonic TH-P65ST60A no STBY light no backlight no power

[JohnML1975]

Hello All

Started working on this TV today
As I remove the back will share some photos and findings
The problem I am having is in the title of this thread
I still need to proceed my trouble shooting
Started a thread so that I can share with all

Any inputs are welcome

[JohnML1975]

Here are photos
There are no burn marks that I can see
The two fuses on the power board are serviceable

I need to check power on the PSU next

[JohnML1975]

Have 347 V at the main filter capacitors which have 450 V written on them
There is no power to the sustain boards even if I disconnect them
I am going to check power to the mainbaord next and leave the sustain boards disconnected

[JohnML1975]

Checked power from mainboard to PSU
there is zero voltage on all 14 pins

I used thermal camera on the PSU and could not see anything standing out

removed PSU and cleaned the dust off
looked around both sides of the PSU board

there are many cracked solder legs on the MOSFETS and transformer legs
these appear to be on the mainboard supply and the sustain board supply

so i am going to resolder every joint, except the SMD joints on the PSU
then shall refit and test

[JohnML1975]

Soldered the suspicious joints and soldered some others that did not look very good
refitted the PSU board
tried to turn on but the failure mode is the same

no power outout

going to remove the PSU again and check components with multimeter

[ivtv1]

Have you measured all the outlets for leaks with a multimeter?

[JohnML1975]

Hello and thank you ivtv1
I am not too sure what you mean
if you could clarify it would be appreciated

The PSU does not produce any power to the mainboard
the PSU does not produce any power to the two sustain boards
So I think there is a problem with the PSU

I completed checking the MOSFETS and the diodes which are through hole components
These are all serviceable

At the moment I am moving on to check the resistors

[ivtv1]

If there is a short circuit in any of the outputs of the power supply, it will not start. With a multimeter, check for a short circuit to ground.