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Equipment Repairs => PLASMA TV forum => Topic started by: Turnip on December 07, 2017,10:28:14

Title: Panasonic TH-46PZ81B - No go, at times.
Post by: Turnip on December 07, 2017,10:28:14
Hi folks,

Got one in where cust insists it's the on/off switch, but don't think it is as switch doesn't handle mains current. Cust says it comes on at times, other times set appears to be off with no Leds.

So far it's been OK for me, coming on every time, even when the set is very cold.

Wonder if it's a candidate for U203(TZS9EK097) as on some other Pana models ? - Chris.
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: t1412 on December 07, 2017,14:29:21
hi chris had a similar fault i panny can't  remember the model of the tv, but i changed ic and a zena diode underneath the psu,  the tv was fine after that,cheers

shaun
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: downunder on December 08, 2017,04:39:24

Greetings Chris, from the nether regions,

Power supply on these has been incredibly reliable except for the monolithic chip cap (1uF) on the small modules MC201 and MC301, but these caused code 2 and 10 respectively, and can be intermittent.

Could also be clogged or sluggish fan, but again this causes code 11. Don't suppose the punter mentioned a blinking red LED. I think dirty LVDS plugs/sockets can cause intermittent loss of picture - sound remains. Try wriggling plug P7 and corresponding plug on the other end of the loom and see if it affects the picture.

Otherwise you're on your Pat Malone - balls in your court.                        Bruce
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: Turnip on December 08, 2017,07:53:36
Thanks Shaun and Bruce,

When faulty, set shows no Led activity, no nice error codes. Mentioned U203 as it seems to cause the exact same issue on other Pana plasma sets of that vintage which may have a different power board.

Set hasn't actually gone wrong for me yet. Came in with the on/off switch covered as they thought it faulty and turned it on/off at the wall. Guess after a while it didn't come on from the wall either so they brought it in - Curious - Chris.

Later - Downloaded the manual and couldn't find module U203 with it's TZS9EK097 chip, so guess a different P/S.
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: downunder on December 21, 2017,05:39:37

Hi Chris,

An erudite tech across the ditch (NZ) advises that the power switch on these does gives problems - goes high resistance enough to cause the TV to switch off and on. For future reference in case it ventures your way again.

Bruce
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: Turnip on March 02, 2018,09:30:26
Thanks Bruce,

Chap who does the leg work took it back to find the mains extension socket rather Brown, and the set wouldn't come on. Not a word since - Chris.
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: ProDave on June 18, 2018,12:04:03

Greetings Chris, from the nether regions,

Power supply on these has been incredibly reliable except for the monolithic chip cap (1uF) on the small modules MC201 and MC301, but these caused code 2 and 10 respectively, and can be intermittent.

Anyone care to point me at which cap? I have a set in at the moment with a code 10 and it has to be worth a punt trying that.
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: downunder on June 18, 2018,15:56:42

Here you go Dave,

The blue cap on the upright module MC301 is usually the culprit. The original is a tiny chip cap off pin 13 of the ic. Do not replace it as has been done in this case. Merely remove it from the module.                Bruce
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: ProDave on June 18, 2018,16:36:10

Here you go Dave,

The blue cap on the upright module MC301 is usually the culprit. The original is a tiny chip cap off pin 13 of the ic. Do not replace it as has been done in this case. Merely remove it from the module.                Bruce
Thank you, you are a flippin genius!!!!

I was on the verge of ordering the repair kit which wa a new SMD chip and a new capacitor. So I thought I would try your suggestion and just remove the offending cap.

The set is working!!!!!

Do I just leave it like that and give it back to the customer, or fit a new cap?
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: downunder on June 19, 2018,03:05:17

Hi Dave, just leave it as-is. The set will functions quite merrily without it. We used to replace them but it was a tricky manoeuvre
given the size and flimsy nature of the solder pads.

So that cap on MC301 causes code 10, cap on MC201 (identical) causes code 2. An invite to a roast dinner would be nice except we're worlds apart.

Bruce
Title: Re: Panasonic TH-46PZ81B - No go, at times.
Post by: ProDave on June 19, 2018,03:29:41
Which part of Down Under are you? I have relatives in Queensland a bit north of Brisbane and been over there twice.

This must be the first time a set has gone back with fewer components than it arrived with.