Samsung PS43D450 Plasma - Very strange VS and VA?

[mrpipes3]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

So I have a similar problem. Originally I had no power. Took the back off look at all the caps, nothing obvious. The the power came on and I had sound but no picture. I replaced the board where you plug HDMI cables, and the logic board. Still sound but no picture. Then I switched back to my original HDMI board and logic board. Still sound no picture. I just got a new power supply today and it reads around 70 max on the VS. VA reads good. The sticker says VS should be 208. The TV powers on....no sound or picture and shuts off after clicking. I adjusted the VS up and down and still about the same reading of 70. I have used X and Y boards. Should I put them in? Would a bad X or Y board cause a low VS reading? Which board should I try first? Thank you!

[tom66]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

How are you measuring Vs? It sounds like your power supply is bad, but the low reading can be caused by a cheaper multimeter that is subject to interference from external sources, like the TV. Can you borrow another multimeter for a "second opinion"?

[mrpipes3]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

So I have a similar problem. Originally I had no power. Took the back off look at all the caps, nothing obvious. The the power came on and I had sound but no picture. I replaced the board where you plug HDMI cables, and the logic board. Still sound but no picture. Then I switched back to my original HDMI board and logic board. Still sound no picture. I just got a new power supply today and it reads around 70 max on the VS. VA reads good. The sticker says VS should be 208. The TV powers on....no sound or picture and shuts off after clicking. I adjusted the VS up and down and still about the same reading of 70. I have used X and Y boards. Should I put them in? Would a bad X or Y board cause a low VS reading? Which board should I try first? Thank you!

So I'm an idiot. I was testing the VS and VA in AC mode. I stuck my original components back in and a new (used) x sustain and (used)y sustain board. I tested with multimeter in DC and the VS and VA check out. Only think is I ripped the ribbon on the x sustain board when putting it in. Thoughts?

[tom66]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Put the ribbon back in and try it again? Did you damage the actual ribbon? They are removable.

[prince_akg]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

I am trying to find solution for my samsung plasma model 42" SD s4.0 ...No picture , with in a few sec smps relay clicking sound comes turning gree led indication to red.

have checked smps (LJ44-00092E) voltage leves, only low voltage are maintained (Vg,D5V,D3V3,12V-amp ,A12/D12,Vt,5v-STB, except Va=70v but all other high voltages are 0 or equivalent, , Vs,Vscan,Vset,Ve =0v

[r2d2hp]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

I have a similar problem to pin6pts and wondered if he ever resolved the problem.
Yesterday I was watching my PS59D6900 and there was a crack sound and the TV powered of and then came back on but screen is blank. The remote still works and can change channel, level, and power of the TV but its not possible to turn back on and the standby light is off. If I cycle power the TV comes back on. I then took the back off and checked some voltages and found VS,VA & VS_on are 0V. If I check the voltages after recycling the power I can see they are there for about a second. Any thoughts on what might be wrong? thanks

[zens electronics]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Hi

These D series Samsung plasma sets are notorious for panel failure .

Had them fail as you described , with a small crack .

Regards Xen

[zens electronics]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Just to clarify , i'm refering to the PS43D450

[dick_barton]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

I have a similar problem to pin6pts and wondered if he ever resolved the problem.
Yesterday I was watching my PS59D6900 and there was a crack sound and the TV powered of and then came back on but screen is blank. The remote still works and can change channel, level, and power of the TV but its not possible to turn back on and the standby light is off. If I cycle power the TV comes back on. I then took the back off and checked some voltages and found VS,VA & VS_on are 0V. If I check the voltages after recycling the power I can see they are there for about a second. Any thoughts on what might be wrong? thanks

With the set off use you meter and check the resistance between VA and ground and Vs and ground.

[r2d2hp]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Thanks Dick

Found resistance between VS & Ground was 1 ohm. After disconnecting boards one by one traced problem to X-Drive. When I power on now VS & VA rise to normal levels and they decay very slowly unlike before when it dropped to zero immediately.
Still not able to turn TV back on once turned off and it does power on immediately when applying power so maybe its got another problem as well.
Found an X-Drive board so will update once it arrives

[dick_barton]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Have you read post #30

[r2d2hp]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

I missed that one Dick, thanks. Will disconnect Y-Drive ribbon cable and see if Voltages stay high.

Question for Zens, have you ever known screens to crack on their own or is always as a result of impact?

[zens electronics]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Yes , have on several occasions had plasma displays crack on their on , without any external impact .

Normally the inner part of display .

This is a phenomenom that i have noticed ever since plasma displays became slimer .

Never had this scenario with the older , more chucky displays.

[r2d2hp]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

There was a crack sound before it went off. When the screen cracks does it normally take out the circuit boards?
Will have a close look at it tomorrow

[zen]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Yes

Display normally develops some sort of internal short & can potentially take out buffer boards plus y-s u s .

I wouldn't waste any more time on it .

[r2d2hp]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Removed cable as per post #30 and VS&VA rise to correct levels. Remote now also turn TV on/off.

Can not see any cracks on external part of the screen and difficult to see what is behind the metal panel.

Will await the arrival of the X-Drive and see if that resolves the problem

[r2d2hp]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Well Zen, X-Drive arrived, fitted and all voltages came up. However after about 40 seconds large crack and flash from Z-Drive. X-Drive appears to to be working and VE voltage is good. VSC is bad. Could problem with X-Drive have also damaged Y-Drive. Thinking its probably time to throw in the towel.

[zens electronics]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Yes display can take out the Z SUS board also

[r2d2hp]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

I could not give up on her and found a replacement Z-Drive. All fired up but then TV fell
foul of the dreaded boot loop. Sent the main board away for repair to https://www.ebay.co.uk/usr/louise.cole19862012 Service is fantastic - there and back in 4 days. Now working again so fingers crossed she will last a few more years

[dick_barton]

Re: Samsung PS43D450 Plasma - Very strange VS and VA?

Thanks for the follow up. Glad you got there in the end.