VESTEL 17PW25-4 250111 V1 PSU - Project

[Fred53]

Hi All,

I have attached some pictures of this VESTEL 17PW25-4 250111 V1 PSU removed from a Toshiba 32BV702B.

TV worked fine from new (10 months old) it had a blank screen and red flashing light on start up, performed factory default reset as advised by Toshiba and all was ok for three months.... Now13 months old and Toshiba don't want to know.

TV was in PC mode VGA connected, when I shut it down / standby / no on off switch.
Next morning the set was totally dead, stripped it down and found the PSU Board is Fried, Blown apart IC (see Pictures).

Q1. Is this failure common on this PSU and is there likely to be another / different panel fault that caused it?

Q2. I have got another working 17PW25-4 250111 V1 PSU (See Pictures) from a 26" if I remember rightly.
What are the Chances of it working if I swap out and replace all different components, caps, etc from the blown board to the working board, it seems to be half a dozen caps to be changed or repositioned and the toggle switch socket needs bridging?

I have examined it closely and everything else seems to be the same underneath, a standard board with different positions for components and caps to make life hard.

(I am of work sick at the moment, so it will pass some time)

Any and all feed back would be appreciated, before I start this project. Thanks Fred.

[tom66]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Sigh, another one of these. I've had three of these PSUs in 6 months. All with same fault. Though usually not as catastrophic.

Has a serious design flaw due to penny pinching:
https://www.badcaps.net/forum/showth...light=17pw25-4

It's NOT a Toshiba, it's a Vestel set same as Alba, Bush, Technica, Digihome etc. Toshiba just rebadge and add big markup.

The 26" board will work fine. They are interchangeable. You need to check if the jumper "S814" is present (near connector going to main video board). It needs to be same as your old board, if it's present then use a blob of solder if not remove it.

[Fred53]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Thanks for the info Tom, unfortunately my hands and eyes aren't as good as they used to be so I ballsed up the soldering LOL.

Found a New PSU for Toshiba 32BV702B on ebay (lots of good feedback for the same board) for £41 incl shipping, so I will have to go for that option

[Skyskovski]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Hi All turned on my digihome32914lcd which has a Vestel 17PW25-4 250111 V1 PSU and nothing happened. Checked the fuse and all was ok so I opened the tv to check for any blown components but could see none. However on plugging the TV there was a bang. still can't see any signs of burning or blown anything. I am more into electrical than electronics so need some help as to what action (apart from just getting a new board) that I can take and what to look at to replace. The sticker on the board has the following (23012666 - 26989618 2112). Pics attached

[Alastair E]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Charles Hyde and Son supply these new for about £40 in the UK....

They really ARE a Cruddy piece of poo these Vestel PSU's!

Here's one example they supply---

http://www.chsinteractive.co.uk/elec...0-mb60-dvd.htm

[Fred53]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

THIS MIGHT BE THE ONE YOU NEED

http://www.ebay.co.uk/itm/17PW25-4-2...item4180e00bcf

[Klockaren]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Hi,
I'm a little bit confused about the schematics for 17PW25-4. I have downloaded the schematics from some sites, but none of them are correct compared with my board.
Does anybody here have some correct schematics for VESTEL 17PW25-4 250111 V1?

Regards Gunnar

[selldoor]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

This is one tom66 has

If you have read some threads re Vestel by now you should realise that
the boards regularly do not match schematics - they seem to implement layout changes and component changes using the same board number.

If you need help it is probably best to post good clear pictures of your boards
front and back and detail of your problem including what the set does from plug in- switch on and so to fault position

[tom66]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

The schematic seems to code for at least 50 different possible versions of the 25-4, so you have to figure out what parts to ignore on your own. Sorry!

[Klockaren]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Thanks for your support!
I have a problem with R980 wich is partially burned. I can see a little bit of the marking so I think it could be 15R. I will gamble with that.
R923 is 100R on my board, but 15R in the schematic so therefore it feels insecure to trust at values in the manual.

[tom66]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

I believe those are 0.15 ohms....

[Klockaren]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

I believe those are 0.15 ohms....

No I dont think so, 15R means 15 ohm. I can see some rest of the markings 150 which means 15 ohm.

[selldoor]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Ok not sure where i am going with this - started to look for other 15Rs on the schematic but only found 3.

R923 R 980 R987 are all 15R on the schematic
Are they all 100 ohms on the board If any one is not can you physically test it
to see what ohms it has?

R822 R823R826 R827 are all10R on the schematic- Are they !0ohms
on the board

[Klockaren]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Hi guys,

Now I'm really pissed off for this bad PSU design.
I replaced the brokebn resisitors and the TV started...jippie

Then I checked the forward voltage drop of the 8 pcs 1N5402 and discovered that the one that I had replaced earlier, had a much higher voltage drop than the others.
I decided to replace all 8 with new ones from my stock. They differed from 543mV to 555mV (12mV), but I decided to try that.
I restarted the TV again and after about 10 seconds I checked the temperature of the diodes and found that the diod with the highest forward voltage drop were quit hot.
But before I had done that I heard a noise from a spark in the diode region.

After checking some components I found out that the diod with the highest voltage drop were shorted and Q935 and the fuse were broken. Maybe som more components hav gone to h..l
I consider to throw the shit away, but maybe I will try to find a large to replace the 8 with to override the miserable construction.

[tom66]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

It really is a dreadful, horrible power supply to repair. In future, consider using a series light bulb, it might save you killing everything at once.

Usually it's the diode with the lowest forward drop that gets hot.

[Klockaren]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

It really is a dreadful, horrible power supply to repair. In future, consider using a series light bulb, it might save you killing everything at once.

Usually it's the diode with the lowest forward drop that gets hot.

Yes you have right!
I just wonder how the designer of the PSU thought, when he made this.
Did he have any education of all in electronics? Was he drunk?
Where there any check at all of this construction?
Many questions that never will get any answers

[tom66]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

See here for how this power supply is a complete failure of design:
https://www.badcaps.net/forum/showthread.php?t=42137

The forward voltage is one issue. The fact that the diodes voltage rating is exceeded by 2.8x is also a problem and it begs belief that any company could release a power supply with such a critical design flaw. The diodes must be replaced with 1000V type for reliability.

Just a look at the schematic will tell you that it was drawn by a complete idiot.

[Klockaren]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Hi Tom,

I will try to use these diodes
BY500-1000

What do you think of that?

[tom66]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

Should be OK.

[selldoor]

Re: VESTEL 17PW25-4 250111 V1 PSU - Project

I would still power it up using a light bulb - google "Dim Bulb Tester"