Re: Panasonic TX-26LXD8 stuck in standby.
Comes up to 2.74vdc and holds steady....
py3m4n
Senior Member
Last Activity: 03-17-2016, 04:26 AM
Joined: 07-20-2011
Location: Stirling
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Re: Panasonic TX-26LXD8 stuck in standby.
I need to go just now but I will do as you asked and update in around an hour.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
Here's a pic of the SCH for IC1104 and a pic of the block diagram where I got the voltages from....Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
It reads - 3C08Q
Panasonic P/N is - C0EBM0000026Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
Do you think the problem could be the resistor I mentioned in post #31?Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
24vdc at these points.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
Yes there is clicking coming from one of them.
24vdc enters the mainboard at connector A7 on pins 7 and 8. There is a separate connector for the 24vdc going to the inverter....Last edited by py3m4n; 03-22-2012, 11:51 AM.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
There is 24vdc at the area circled in red (see pic) but only 2.6vdc at pin 1 and 7.2vdc at pin 2 of IC1104.
Could the problem be that first resistor where the 24vdc is coming in?...Last edited by py3m4n; 03-22-2012, 11:47 AM.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
Pics of PSU are in post #21.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
I tried to to understand what's going on at IC1100 and it has led me to check IC1104 (Reset IC).
Pin 1 should be 3.3vdc - Pin 1 is 2.6vdc stable
Pin 2 should be 24vdc - Pin 2 is 7.2vdc stableLeave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
The power LED comes on then goes off again, definitely no error codes shown.
With just power coming to the mainboard from the PSU and with the power switch connected to mainboard (no other connectors connected) Pin 52 of IC1100 is going Hi-Lo. Don't know how helpful this might be.
Same goes for Pin 18 TP of IC5604 - AG_TV_SUB_ON is Hi-Lo. (I know realise this is obvious by what you wrote)Last edited by py3m4n; 03-22-2012, 10:54 AM.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
I am busy trying to do that for you on the SCH, to go with the pic of the location on the rear, needless to say, brain pain, lol.
That point leads to Q1104. It goes around the edge of the board under the yellow bar that is printed on it.
Edit - Third pic is location of Q1104 on the board....Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
Pictures of PSU.
I have two PSUs for this T.V. The previous owner bought one to try to repair it and had the same symptoms. I tested the PSUs and ruled them out, as both are outputting the correct voltages shown going to the main board and inverter on the SCH. The don't change under load....Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
Path of 10k resistor circled in red on rear of board.
Vin is Hi-Lo....Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
Vc is steady - 3.69vdc.
At Vo with jumper in place - Hi-Lo.
Meter at point shown in diagram is indeed going Hi-Lo.
Indicator lights - I had hoped for this to be the case when I bought it because the service manual has the section covering it, no luck. The red standby light comes on and goes off immediately, no error codes to be had.
I am currently working on tracing where the 10k resistor you mentioned leads us, I will update soon.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
Checked RELAY_5V6 using the test point from emitter of Q5607 (see pic)
RELAY_5V6 - 5.48vdc - 5.55vdc
STB_5V6 - 5.4vdc steady
With jumper in place. 3.5vdc @ collector of Q5605.
Here's the frustrating part, after I did this I retested the Vo of IC5602 and now it's going Hi-Lo ?!?! (jumper was removed)
Now has me wondering if I have done something to cause this....Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
Did as you said. I used the emitter of Q5609 as ground.
Q5608 Base and collector are both going Hi-Lo.
B - 0vdc - 0.4vdc
C - 0vdc - 5vdc
Collector of Q5607 is 0vdc - 2.7vdc.
Just as you described!
Now I see you have made it easy. I appreciate it, although I was kind of enjoying the brain pain, lol.
Cheers bud.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
I have been using the screw in the top right of the mainboard as my ground point.
The readings I took on R5654 were after removing the short, same for the rest. The only reading I took whilst the short was in place was at the Vin of IC5602.
Q5605 is an NPN type transistors, is that right.
Having to differentiate between which transistors are NPN and PNP from the schematic and using the SCH in conjunction is hurting my head, but the only way I will learn is to persist!
Edit - I have just...Last edited by py3m4n; 03-21-2012, 12:47 PM.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
@budm
Shorted R5654, no change, still clicking going Hi-Lo.
Took voltage readings at the left and right pins of R5654.
Left pin - 0v
Right pin - 0.5 - 0.65 Hi-Lo.
Took some other V readings not sure how helpful they will be.
Q5608 -
0v - 5.55v Hi-Lo @ collector.
C5671 -
5.55v @ Top pin/Pos
0v @ Bot pin/Neg
Q5610 -
Pin 1/Source - 5v stable
Pin 4/Gate - Hi-Lo.
Pin 5/Drain - Hi-Lo....Last edited by py3m4n; 03-21-2012, 11:52 AM.Leave a comment:
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Re: Panasonic TX-26LXD8 stuck in standby.
@budm
Just to double check, is the resistor circled in the attached picture the correct one I want to short....Leave a comment:
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