panasonic tx42-p42x20b

[adamp91gvm]

Re: panasonic tx42-p42x20b

i have taken everything off the power board apart from the power lead and the main lead to the a board and still 10 flashes

[SCITOMMY]

Re: panasonic tx42-p42x20b

Do you have fans? Do the fans spin at all on powerup? Is their any signs of life that the power supply is working? If it does, then it's most likely the A Board.

[SCITOMMY]

Re: panasonic tx42-p42x20b

Also, do you get any illumination, glow or dim on the screen at powerup? If you do, it's definitely the A-Board.

[tw2005]

Re: panasonic tx42-p42x20b

That would suggest either A or P, I'm away for 3 weeks from home, don't have all the manuals and guides I'd refer to so someone else may have to help out.

If you have the manual I'd check the 5V and 15V. Could PSU but I'm thinking something on the A may be shorted or dragging the voltages down.

I have had 10 blink on this model caused by the 5V dragged down by some C541 20pin buffer ICs.

If you can figure out how to jumper the PSU to turn it on without the A you could check the voltages.

Maybe have a dig in Toms pile of material, might find a training guide in there that's close. 2009 models might be close enough for that in the guide.



http://www.toms-service-manuals.com/...&typekey=2&p=2

http://www.tgohome.com/ServiceManuals/

I'm thinking P6 on the PSU checking for 15v,

1.
Missing/Shorted F_STB_15V, SUB9V, SUB5V, and BT30V
2.
Wrong diagnostic by the A board

That's out of the guide slide 31

10 blinks Condition Troubleshooting
1.
Missing/Shorted F_STB_15V, SUB9V, SUB5V, and BT30V
2.
Wrong diagnostic by the A board
Since the Sub voltages are only present after the power has been turned on, there will not be a 10 blinks condition at plug-in for the 2009 models.
These 3 conditions can cause the TV to shutdown and the power LED to blink 10 times
To troubleshoot a PDP TV that is shutting down and the power LED blinks 10 times:
 Find out if 15V is output at pin 7,8,or 9 of connector P6 of the P board. If no voltage is output, the P board may be defective.
 If the F_STB_15V voltage is OK, it’s likely that the A board is defective.

Sorry mate, best i can do for now but my gut tells me A board but once you can confirm the voltages from the PSU are ok that will verify which board.

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[adamp91gvm]

Re: panasonic tx42-p42x20b

what ever help is much appreciated thank you so much for your time im trying to get a tester from work to check the caps too

[tw2005]

Re: panasonic tx42-p42x20b

what ever help is much appreciated thank you so much for your time im trying to get a tester from work to check the caps too

Well generally speaking PSU and CAP issues especially electrolytics in the Panasonics are rare. They use quality brands like Panasonic, Nichicon and Rubycon .

Not to say they can't have issues but in the latest models they really started to strip the budget models down a bit and use other brands I suspect to reduce costs and now they've stopped production of plasma AFAIK.

I've read of 2 troublesome PSUs, 2007 models with a FET that shorted out and 2008 early 2009 PSUs which had 2 modules where a 1uF ceramic failed and caused 2 & 10 blink.

Nothing sticks to mind for the 2010 PSU, If the correct voltages are present out of the PSU then has to be A board.

See how you go.

[tw2005]

Re: panasonic tx42-p42x20b

If you back probe the 15V from the PSU and it's there on startup, I'd be leaning towards A.

[tw2005]

Re: panasonic tx42-p42x20b

service manual Tx-P42X20

Block diagram p34 shows P6, pins 7,8,9 for 15V which the A board uses for creating the SUB voltages. Q5471 monitors the SUB 5V,SUB 9V and switches the SOS10 on.

P61 has that cct and the ICs for generating the sub voltages.

[adamp91gvm]

Re: panasonic tx42-p42x20b

Hi I have spoken to the ladie who last owned this tv and she said she put a smile card into the tv and it went off so I'm thinking it's the A board but can not find one anywhere in the UK or this model tv as spares or repair on ebay gumte or preloved

[tw2005]

Re: panasonic tx42-p42x20b

Hi I have spoken to the ladie who last owned this tv and she said she put a smile card into the tv and it went off so I'm thinking it's the A board but can not find one anywhere in the UK or this model tv as spares or repair on ebay gumte or preloved

what on earth is a smile card?

[adamp91gvm]

Re: panasonic tx42-p42x20b

Sorry sd predicted writing lol

[tw2005]

Re: panasonic tx42-p42x20b

Is there anything stuck in there to short it out or bent contacts shorting?

[adamp91gvm]

Re: panasonic tx42-p42x20b

Not that I can see but the cover is gone off the top of the sd port

[tw2005]

Re: panasonic tx42-p42x20b

Apparently kids like putting coins in that slot

I have read a couple of cases where foreign objects have been found in there shorting it out, having been removed restored the A board back to normal.

Sounds sus if the cover is off, maybe it was not a SD inserted into it.

The A is probably repairable, sounds like it will be a 5V issue.

[tw2005]

Re: panasonic tx42-p42x20b

there's only 3.3V for the SD. Page 50 , search JK8850 for pinouts

[tw2005]

Re: panasonic tx42-p42x20b

Page 61, IC5601 generates the Sub 3.3V & 5V from the 15V by switching Q5605 for the 3.3 and Q5604 for the 5V. Looks like there's some fusible resistors around that.

R5639,5635,5634,5648,5638,5647,

[adamp91gvm]

Re: panasonic tx42-p42x20b

I'll have a good look in the morning fingers crossed I'll Keep you posted thank you

[adamp91gvm]

Re: panasonic tx42-p42x20b

From p6 I'm getting:

1: 0v
2: 0v
3: 15.5v
4: 15.5v
5: 15.5v
6: 0v
7: 0v
8: 0v
9: 0v
10: 0v
11: 0v


That's from left to right on p6

[adamp91gvm]

Re: panasonic tx42-p42x20b

P7 I'm getting :

1: 4.8v
2: x
3: 4.8v
4: 0v
5: x
6: 0v
7: 0v
8: 0v
9: 0v
10: 3.1v
11: 0v
12: 0v
13: 0v
14: 4.8v

That's the same left to right

[tw2005]

Re: panasonic tx42-p42x20b

From p6 I'm getting:

1: 0v
2: 0v
3: 15.5v
4: 15.5v
5: 15.5v
6: 0v
7: 0v
8: 0v
9: 0v
10: 0v
11: 0v


That's from left to right on p6

If that's at the PSU and left to right viewed from the rear with the PSU mounted in the TV,that should mean the left most pin is 11. Should be stenciled onthe board next to the connector, should see 11 at one end,1 at the other.

If that's what you've done that should translate as

11: 0v
10: 0v
9: 15.5v
8: 15.5v
7: 15.5v
6: 0v
5: 0v
4: 0v
3: 0v
2: 0v
1: 0v


Pins 7,8,9 at both P6 and A6 are the 15V so it would appear the PSU is supplying the 15V which points us back to the A board where the SUB voltages are generated and monitored for SOS10.