Hello lotas
thank you
I should have treated the 2.2 ohm resistor the same way i would treat a fuse
next time, i will do that
meantime, i have found the shorted part and shared a photo
each leg is shorted to the other leg
the voltage drop is less than 0.03 volt when the DMM is in diode mode
when i check the board the short is now gone
i am going to order the new part
JohnML1975
Senior Member
Last Activity: Today, 01:14 PM
Joined: 07-03-2025
Location: Lidcombe NSW
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I found a shorted MOSFET on the hot side of the board
I will need to remove it and test itLeave a comment:
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I fitted new resistor and the resistor just blows up; there is flash and the resistor becomes open circuit again
so i guess whatever that resistor is connected to is faulty
i shall need to trace that circuitLeave a comment:
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This is the 2.2 OHM resistor removed and tested
It says OL
In the board it measures at around 60 kilo ohms
So i think it needs a new resistorLeave a comment:
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Thank you ivtv1
Today I placed red probe of multimeter on each of the two sustain plugs
I placed the black probe on ground
There was no shart circuit on the power side
next i powered up the board
connected to the two filter capacitors are two resistors
there is 340 V to one side of the 2.2 ohm resistor
there is no power on the other side of the 2.2 ohm resistor
when i check OHMS across the resistor there is OL showing on the multimeter
the resistor looks okay
i will remove it from the board and test itLeave a comment:
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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...Leave a comment:
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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 multimeterLeave a comment:
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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 testLeave a comment:
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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 disconnectedLeave a comment:
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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 nextLeave a comment:
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Panasonic TH-P65ST60A no STBY light no backlight no power
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 -
Hello all
I replaced with new LED strips and the dark spot remained
So I would have to assume this is a panel problem
Have thrown the TV out
Thought I would update since I was unable to repairLeave a comment:
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