Panasonic TH-46PZ800U dead.

[martino]

when you plug it in,relay on powersupply clicks twice,red led on front is off.
Then I push the power button and led comes on solid,no clicks from relays.
It then sits for about a minute,then relay double clicks and it sits again for a minute.then it clicks and the led starts flashing 13 times till you unplug cord.

Downloaded from toms site manual for a 46pz80u(not 800u) as it seems to be pretty much same tv??
13 blink code=Communication error with IC8001 checkpoint A board.

On P6:pin 7,8and 9 I have 15 volt (F-STBY)
On P7:pin 5 I have 5volt (STBY5V)
:pin 6 I have 3.3 volt (F-STBY-On)

No sign of life other then the click of relay and the led.No fans on,no VA VS etc.
It seems mainboard is not even attempting to turn TV on?
Disconnecting Y main and Xmain make no difference.

Looking for a bit of guidance,can I force the TV on without the mainboard?
If so,how? Any test tricks?

I

[tom66]

Re: Panasonic TH-46PZ800U dead.

For a "communication fault" I'd check low voltage regulators on the main board, chances are one is down or shorted.

[tw2005]

Re: Panasonic TH-46PZ800U dead.

disconnect, A5(LVDS cable), A6,A7, power on and produces full white screen, works on my 46PZ800, or A5, P6,P7.
Had to push the power button to turn it on, there will be no front LED indication, not on mine at least.

If the LVDS is left in, mine goes to a gray, primed screen.

[martino]

Re: Panasonic TH-46PZ800U dead.

Disconnected A5,P6 and P7 and indeed get a white screen!!
So,mainboard is target now.
Will check the low voltage regulators on main as per tom's suggestion,will report back

[martino]

Re: Panasonic TH-46PZ800U dead.

poking around on the mainboard,concentrating on this area,see pic#1.
see pic#2 for voltage reading,does that make any sense to you?
pic#3,close up of suspect area with my handy little usb microscope camera

Q5603 and Q5604 =2SD0601ARL=transistor
D5692=MAZ80560LL=zener diode

[tom66]

Re: Panasonic TH-46PZ800U dead.

FSTB+15V det fault would probably cause 2 or 10 blinks.
Have you checked the 3.3V, 1.8V, 1.2V, etc.?

[martino]

Re: Panasonic TH-46PZ800U dead.

Have you checked the 3.3V, 1.8V, 1.2V, etc.?

I'm a little lost in the "how to check that" or better yet"WHERE to check that"


My mainboard is a TNPH0731,the schematics I pulled of your database has the TNPH0721,although very similar,it's a tad different in lay out...
I see a few test points,as in TP3506 sub9v,and one for the 15v but cant find for 3.3,1.8 etc...
Unclear to me which regulator controls which voltage....

[tom66]

Re: Panasonic TH-46PZ800U dead.

Look for SUB3.3V, SUB1.2V, SUB1.8V voltages.
Find any capacitors, test points etc. you can measure near or across.

[martino]

Re: Panasonic TH-46PZ800U dead.

Thank you
Looked a little better at the schematics and low and behold,they even have a powersupply section for the mainboard,that will teach me to look before asking a little more...
Anyways,found all the regulators and all the voltages are present and correct.
9,5,3.3,1.8 and 1.2 volts are all there and stable....

That puts me on the next question,what to do next.........
If I look at IC8001,it's one of those BGA chips,try and reflow?

Took a look at my 50pz80u(with the IR or burn in) and it has the tNPH0721 main board in it,but I dont think the plugs are the same(to just flip boards and see)

[tom66]

Re: Panasonic TH-46PZ800U dead.

If you have a scope, check the I2C/IIC communication lines and clocks to the processors.

[martino]

Re: Panasonic TH-46PZ800U dead.

Well,haha,ya I do have a scope.....sort off......bought one of those DIY kits on ebay that supposed to be a scope,I'm sure it's barely good enough to even turn on but I figured as long as I can see some sort of activity on a signal,it will at least tell me if i have activity.
I got the kit but havent build it yet,so will do that today
http://www.ebay.ca/itm/Portable-Digi...item4d0dc8f02b

Now in reality,if i check the I2c/IIC to the processor,and find a fault,that would most likely mean a fubar BGA chip? I'm not capable to reball or replace one of those.
Did you have any luck repairing this area of the main board? I would love to be a little more capable in the mainboard area as I replace too many that I'm thinking could be repaired....