TH-42PZ70BA 10 bllinks not intermittent

[tw2005]

Re: TH-42PZ70BA 10 bllinks not intermittent

Fixed it was that thermal fuse.

cool, which one? so the TV runs now, no blinks. That's one to learn from.

[tom66]

Re: TH-42PZ70BA 10 bllinks not intermittent

One embedded in VSUS transformer.

Runs great, has 8000 hours on it. No burn in, no maldischarge.

Probably going to tweak black level down, it's quite a lot higher than my PZ80. But it is also a lot brighter. Then again it's rated for around 600W instead of 470W.

[tw2005]

Re: TH-42PZ70BA 10 bllinks not intermittent

not shown in the schematic? you're a clever dick.

[tom66]

Re: TH-42PZ70BA 10 bllinks not intermittent

It is...
Tested at 20Megs so pretty close to open circuit.

No load current flows through it, purely a thermal sensor. Odd that they'd bother, given all the other sensors. Just used a spare thermal fuse from my parts bin.

And it's per that other memory of that video:
http://www.youtube.com/watch?v=qQ_iLxx3Fj4

[tom66]

Re: TH-42PZ70BA 10 bllinks not intermittent

Black level maybe 10% lower, not much room for tweaking:

Vsus: 208V
Vset: 362V (factory)
-Vad: -130V
Vscn: 136V
Ve: 155V
Vda: 75V (factory)

Vda only rises after a few seconds of fans running.

[vinceroger69]

Re: TH-42PZ70BA 10 bllinks not intermittent

cool glad you fixed it tom thats a good you tube video showing the fault with those transformers at least u will know next time if you get the same fault how do you check how many hours they have run as will check mine.

[tom66]

Re: TH-42PZ70BA 10 bllinks not intermittent

Checking hours:
Hold VOL-/CH- on TV
Press "0" three times on remote
Release VOL-/CH-

After a few flickers, the service display appears.

The hours and minutes are shown under "Time", bottom right corner. The "Count" is the number of turn on/off cycles (on some models, this also includes the standby DVB guide update as well as record mode, so can be very high.)

I had over 13,000 hours on one set, still playing great.

To exit display, turn off TV.

[vinceroger69]

Re: TH-42PZ70BA 10 bllinks not intermittent

cheers tom will check tomorrow.

[tom66]

Re: TH-42PZ70BA 10 bllinks not intermittent

Diagnosis video:
https://www.youtube.com/watch?v=mBw8q33pqj4

[tw2005]

Re: TH-42PZ70BA 10 bllinks not intermittent

I got a Q because I'm not getting something. If the fuse was in T201 vsus, how does that tie on with T301 for Vda? I have not watched the video yet.

[tom66]

Re: TH-42PZ70BA 10 bllinks not intermittent

Has nothing to do with it - it was waiting for Vsus to rise, could not see it rise so then dying. So it never got to fire up Vda. Vda only comes up after a second or so of fans spinning.

The fuse is only an indicator, it does not carry any load current.

[tw2005]

Re: TH-42PZ70BA 10 bllinks not intermittent

Has nothing to do with it - it was waiting for Vsus to rise, could not see it rise so then dying. So it never got to fire up Vda. Vda only comes up after a second or so of fans spinning.

The fuse is only an indicator, it does not carry any load current.

Yep, just got to the juicy bit about the sus out sense. That's a very tricky one. Really impressed

[tom66]

Re: TH-42PZ70BA 10 bllinks not intermittent

Wouldn't have happened without Gavin's video though.

[tw2005]

Re: TH-42PZ70BA 10 bllinks not intermittent

Still a good effort, real nuts and bolts diagnostics. Makes me wonder with the recent SOS12 15Vsound missing if there's something to be learnt with a sense line missing?

Pity about the money spent on the DG, at least the final remedy was nil.

It was interesting theory about the SOS blinks and the hierarchy. I often wonder about that myself ever since I had that 4 blink masking a 1 blink.

I do think though it all depends at what part of the startup sequence something is detected.

[tom66]

Re: TH-42PZ70BA 10 bllinks not intermittent

I have returned the board to seller who accepts fault-free returns with no restocking fee (only pay postage.) I was able to test it for them and confirm it is fully working too as I put my original DG back in and everything works.

Interestingly both boards had near same hours - 8000 hours vs 7850 hours.

[tw2005]

Re: TH-42PZ70BA 10 bllinks not intermittent

I have returned the board to seller who accepts fault-free returns with no restocking fee (only pay postage.) I was able to test it for them and confirm it is fully working too as I put my original DG back in and everything works.

Interestingly both boards had near same hours - 8000 hours vs 7850 hours.

Bonus, I guess you're regular customer. Win all round. It's good to hear.

[vinceroger69]

Re: TH-42PZ70BA 10 bllinks not intermittent

Checking hours:
Hold VOL-/CH- on TV
Press "0" three times on remote
Release VOL-/CH-

After a few flickers, the service display appears.

The hours and minutes are shown under "Time", bottom right corner. The "Count" is the number of turn on/off cycles (on some models, this also includes the standby DVB guide update as well as record mode, so can be very high.)

I had over 13,000 hours on one set, still playing great.

To exit display, turn off TV.

time 11808:30 so not bad at all

[tom66]

Re: TH-42PZ70BA 10 bllinks not intermittent

yep about 12,000 hours; these panels should reach 50,000 hours easily.

[vinceroger69]

Re: TH-42PZ70BA 10 bllinks not intermittent

cool thats good to here good job also to the people who take time to do the you tube videos showing these fixes imo.

[tn245]

Re: TH-42PZ70BA 10 bllinks not intermittent

Out of interest tom, how much would you want/expect to sell this one for?