TV Panasonic TH-50PZ85U 2 blinks

[Mishannya]

I have TV Panasonic TH-50PZ85U, PS ETX2MM704MGU with 2 blinks issue.
Does anybody have idea about this? Any help or ideas would be greatly appreciated. Thanks.

[retiredcaps]

Re: TV Panasonic TH-50PZ85U 2 blinks

I have TV Panasonic TH-50PZ85U, PS ETX2MM704MGU with 2 blinks issue.

Possible service manual at

http://elektrotanya.com/

PS. How is the 28 inch Hanns-G running? It has turned into a megathread now.

[tom66]

Re: TV Panasonic TH-50PZ85U 2 blinks

2 blinks indicates 15V SOS (failure.)

This probably indicates a problem with the power supply.



Page 47.

Start by taking pictures.

[Mishannya]

Re: TV Panasonic TH-50PZ85U 2 blinks

Here is the picture of PS.

[tom66]

Re: TV Panasonic TH-50PZ85U 2 blinks

Thank you for posting a nice, clear photo. Makes a change for other posts on this forum.

It looks like this power supply doesn't have a standby supply, just a main supply and a high voltage power supply.

Are there any other power supply boards. Anything connected to the 2 pin P54?

Are there any labels next to the connectors, on the top or bottom, which might indicate voltage test points?

Do you have a multimeter?

[Mishannya]

Re: TV Panasonic TH-50PZ85U 2 blinks

Here it the picture of another power supply board, and some more closed view pictures.

[tom66]

Re: TV Panasonic TH-50PZ85U 2 blinks

Okay, that looks good - there's a standby supply on there.

Can you check the voltage on each of the pins at P55 with the board installed in the TV?

[Mishannya]

Re: TV Panasonic TH-50PZ85U 2 blinks

I can't do it right now, cause I far from the TV set. I'll be available to do it later. Thanks.

[rayrod81]

Re: TV Panasonic TH-50PZ85U 2 blinks

The 2 blinks and 10 blinks error code on these Panasonics are related to the MC201 and MC301 stand up boards on the Power Supply. They are controllers for the 15V line and the 15V stand-by. There is a small SMD ceramic cap on each of these boards that is prone to failure. I can't remember which cap it is but if you can get good clear pictures of MC301 and MC201 I should be able to tell you.

If I remember right MC201 is related to the 2 blink error and MC301 is related to the 10 blink error. While you can fix just one or the other I would replace the cap on both boards because when one fails the other is usually soon to follow. I will look through my info for the value of the cap that fails and get back to you.

[Mishannya]

Re: TV Panasonic TH-50PZ85U 2 blinks

More pictures of MC201 and MC301 added.

[tom66]

Re: TV Panasonic TH-50PZ85U 2 blinks

These little brown/beige devices are ceramic capacitors.

With power OFF and TV unplugged from the power socket, use your multimeter to test the resistance from one end to the other. Set your meter to the 200 ohm range.

If you see a reading of less than 10 ohms, I would say the capacitor is shorted.

If you meter shows a single "1" on the display, this does not indicate a resistance of 1 ohm, but confusingly >200 ohms resistance, a good capacitor would show this, as would probes which are not touching.

[rayrod81]

Re: TV Panasonic TH-50PZ85U 2 blinks

Normally a shorted ceramic cap would indicate it is bad but the ceramic caps on these boards become leaky and do not allow the voltage to rise high enough to reach the threshold voltage and turn on the controller IC. It will not read shorted or bad on any meter but it is most likely bad.

If you are looking at the boards from the side with the controller IC it is the cap near the top left corner of the IC. I would recommend replacing that cap on both boards or you might have to open it up again in a few days to replace the other one. I have not found the value of the cap but will let you know when I find it.

[Mishannya]

Re: TV Panasonic TH-50PZ85U 2 blinks

Meter shows: >200 ohms - @ 200 ohm range, >2000 ohms - @ 2000 ohm range in one detection and 688 ohms @ 2000 ohm range in opposite detection. Thanks.

[rayrod81]

Re: TV Panasonic TH-50PZ85U 2 blinks

Ok I found the value. It is 1uf. It is only handling 13.5V but I would recommend a 50V cap to be safe. Just make sure that it is the right size. Like I said you will not be able to find anything wrong with this cap on a meter or cap checker but it is bad. It is leaky and therefore the voltage does not rise to the 13.5V that the IC needs to turn on and in turn the 15V will not turn on giving the 2 blinks. I would recommend replacing the cap on both boards.

[Mishannya]

Re: TV Panasonic TH-50PZ85U 2 blinks

Which cap on the other board? Thanks.

[rayrod81]

Re: TV Panasonic TH-50PZ85U 2 blinks

Same one on both boards.

[Mishannya]

Re: TV Panasonic TH-50PZ85U 2 blinks

It's hard to find 1.0 uf 50v SMD 0603. Are you sure about capacity? may be 0.1 uf. Thanks.

[tom66]

Re: TV Panasonic TH-50PZ85U 2 blinks

It's hard to find 1.0 uf 50v SMD 0603. Are you sure about capacity? may be 0.1 uf. Thanks.

http://search.digikey.com/us/en/prod...64-1-ND/587472

Assuming it is 0805: (0.08" x 0.05" -> 2mmx1.2mm)

[Mishannya]

Re: TV Panasonic TH-50PZ85U 2 blinks

10000pF - 0.01uF instead of 1.0uF? ... Hmmm Please check this part ... Thanks.

[tom66]

Re: TV Panasonic TH-50PZ85U 2 blinks

10000pF -0.01uF instead of 1.0uF? ... Please check this part ... Thanks.

Good point! I'm not paying attention. That looks fine.