Panasonic TH-42PX80E ten blinks

[PowerAmpFreak]

Hioyo!
Panasonic plasma TH-42PX80E suddenly show ten blinks during start-up.
As far as I can see, only standby PSU is on generating +5V and +13V.
It never tries to start up VA/VS supplies.
Never worked much on Panasonics.
Advice?

[Alastair E]

Re: Panasonic TH-42PX80E ten blinks

Disconnect the dual-row plug near the tuner.

Re-try starting the set up, --with the set I had, it then started up and initialised the panel--however, no picture...
It proved the panel and drive electronics/PSU were OK in my case....

[tom66]

Re: Panasonic TH-42PX80E ten blinks

+13V is low for a PSU that should output +15V, are you sure about that? As sometimes there is a +12V rail derived from it this could trigger a fault.

[PowerAmpFreak]

Re: Panasonic TH-42PX80E ten blinks

Yep, the +15V line reads +13,3V. The +5V line is +4,98V.

[PowerAmpFreak]

Re: Panasonic TH-42PX80E ten blinks

Just found out the PFC controller IC was blown.
So, probably it tries to startup the LLC a short time to verify and trig the protection.

[Alastair E]

Re: Panasonic TH-42PX80E ten blinks

There was someone--one of those parts vendors on ebay selling kits for the
PSU's of PX80's, and in one listing they had all the reference numbers of all the parts....

Think the kit for 'em was about £40 if I recall correctly....

edit--

Here's whats in that kit--

F401 F402 C443 C444 Q406 R493 R439 R448 R449 R411 IC406 D431 PR402 R436

The kit-

http://www.ebay.co.uk/itm/PANASONIC-...item2573e15747

[tom66]

Re: Panasonic TH-42PX80E ten blinks

If the PFC bus voltage is low, then it's quite possible the 15V rail won't be able to fully regulate.

[PowerAmpFreak]

Re: Panasonic TH-42PX80E ten blinks

If the PFC bus voltage is low, then it's quite possible the 15V rail won't be able to fully regulate.

Nah! The +15V line is coming from the standby supply. It operates without PFC, through rectified AC, when the set is in standby.

[tom66]

Re: Panasonic TH-42PX80E ten blinks

Yes, but not always. It could be that when under full load (such as when the SC and A board try and run, drawing a couple amps total) this could start loading the rail excessively for a low PFC bus.

Most supplies are designed so that they are regulated on only one rail which is dominant. In most cases it will be the 5V rail. When the PFC voltage is low, the other rails might drift out of regulation (certain assumptions about the input voltage are normally made.)