I have here a second TX-P42S10B 42" Full Hd Plasma tv made by Panasonic, this is another TNPH0784 with 14 blink error code seems to be very common on these boards.
Anyway after finding that the error code which states 14 blink is a Audio Pwm Sos I found that indeed the Audio Pwm cucuit was not working the B+ which is 15v was dropping out causing the tv to go into shutdown.
After reading another thread I found that the most common issue is the ADV7470 Ic that controls the Hdmi and feeds B+ for Audio Pwm was not working. This chip is Bga welded and this tv states how proud it is to use lead free solder (Pb free) so I decided to try and reflow this Ic as nothing really to lose on this tv.
I applied some flux around the edges of the chip and heated it with my heat gun at 500c I heated for about 3 mins notices that the chip and pcb were rasing so turn off heat and let it cool. After hooking it back up the tv works whoooo !
So the failure here was again more crappy Bga solder failing nothing new to me, the tv has been running for hours no issues, I found that this Ic gets very very hot which could have been the reason for failure here as Panasonic did not heatsink the chip. So I found an old heatsink and used silicon thermal plaster to hold it down onto the chip, I also added a heatsink to other large Bga Ic as it got hot but again not heatsinked.
So hopefully this tv will last now, the Ic had not failed but the solder had easy fix but tricky to diagnose. Image is cracking as well. Thanks for reading hope this helps.
I have made a youtube video on the repair it will follow shortly
Image showing mod:
Anyway after finding that the error code which states 14 blink is a Audio Pwm Sos I found that indeed the Audio Pwm cucuit was not working the B+ which is 15v was dropping out causing the tv to go into shutdown.
After reading another thread I found that the most common issue is the ADV7470 Ic that controls the Hdmi and feeds B+ for Audio Pwm was not working. This chip is Bga welded and this tv states how proud it is to use lead free solder (Pb free) so I decided to try and reflow this Ic as nothing really to lose on this tv.
I applied some flux around the edges of the chip and heated it with my heat gun at 500c I heated for about 3 mins notices that the chip and pcb were rasing so turn off heat and let it cool. After hooking it back up the tv works whoooo !
So the failure here was again more crappy Bga solder failing nothing new to me, the tv has been running for hours no issues, I found that this Ic gets very very hot which could have been the reason for failure here as Panasonic did not heatsink the chip. So I found an old heatsink and used silicon thermal plaster to hold it down onto the chip, I also added a heatsink to other large Bga Ic as it got hot but again not heatsinked.
So hopefully this tv will last now, the Ic had not failed but the solder had easy fix but tricky to diagnose. Image is cracking as well. Thanks for reading hope this helps.
I have made a youtube video on the repair it will follow shortly
Image showing mod:
Attached Files
The Tv will boot up and no longer gives 14 blink however non of the HDMI ports work at all. So im just going to replace the board, unless I find a new Chip and someone who can reball it.
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