Vestel 17PW16-2 troubleshooting

[Shotgun25]

Re: Vestel 17PW16-2 troubleshooting

Did you get any further with this repair?

I bought a kit from Tidman (http://tidmanmailorder.co.uk/index.p...roducts_id=256) and I am currently replacing the last two part which are IC806 and IC807.

I don't know how to do all the testing you have done but I have replaced most of the parts you are speaking of.

Here is a list of the parts in the hope it prompts you to a solution.

Text on accompanying A4 sheet.

"Vestel 17PW16-2 PSU Board. Replacing all the components should cure most known faults and improve reliability of the PSU. Based on Hitachi L42VP01U, Technika TVLCD40 & Wharfdale LCD42F1080P"

Kit Contains
F800 - 2.5A fuse
IC801 - PC817 Opto
IC802 - IC FAN7529
IC806 - IC 01653
IC807 - SG3525
C877/8* - Capacitor 15nFd 1000V
R830 - Resistor 0.22ohm
Q803 - Transistor P10NK80ZFP
Q837 - Transistor Yellow (?)
IC825 - IC STPS5L25B
D824 - Diode STTH12 +Insulation kit
D851 - Programmable Zener Diode TL431 (W19)
D836 - Zener Diode Blue (F2J)
D866 - Diode UF5402
C801 - Electrolytic Capacitor 33mFd 50V
C817 - Electrolytic Capacitor 220mFd
C892 - Electrolytic Capacitor 10mFd 50V
*C878 may be 33nFd without C877 in some versions

March 2009

Love to hear back if you managed to fix this.

On a side note, I'd love to know how to test this board - a quick response of whether I can test in-circuit or out of circuit for the parts listed above would be great.

[Shotgun25]

Re: Vestel 17PW16-2 troubleshooting

If you lift out your mosfet Q803 and power on
Does the fuse remain intact
What voltage do you have across C819 pins

I replaced all the parts with the kit mentioned above and the fuse blew.

Having lifted Q803 and the fuse blew again, what would I look for now?

[dskall]

Re: Vestel 17PW16-2 troubleshooting

Check R801 at input

[vinceroger69]

Re: Vestel 17PW16-2 troubleshooting

can you post pictures of the top and bottom of your power supply we may spot something you have missed etc

[Shotgun25]

Re: Vestel 17PW16-2 troubleshooting

I have left Q803 removed as I will need to do some pad repair on the backside of the board to put this back on.

Having found a schematic and searched for R801 that is a good shout since it's the first thing after the fuse.

What type of resistor is it and how should it test? I put multimeter in diode/continuity mode and there were no beeps and there was a reading of 513 with probes connected one way and no reading/ rising reading that turns to infinity after 2000 connected the other way.

IC825 was done around a year ago and it was a pain to get off because I didn't have a decent hot air station to do it (I still don't, cheap eBay rubbish that's 5 years old). As a result pin 1 is not connected but I'm sure from previous research it wasn't connected to anything after the pad or it doubles with the metal back.

IC806 looks like the PCB is scorched, I think that was from the poor hot air station having the airflow set too high with a required high temperature. That is the new chip though and that was hand soldered.

As for all other parts where they look soldered, those will be the parts from the kit I listed above.

[dskall]

Re: Vestel 17PW16-2 troubleshooting

Bridge rectifier is good?

[Shotgun25]

Re: Vestel 17PW16-2 troubleshooting

I've just tested D800 following this video https://www.youtube.com/watch?v=11JPy4t36oo and it shows that one leg from -ve(pin 1) to AC (pin 3) has continuity, the rest were around the 500 mark which is supposed to be in tolerance (400 to 600) according to the video.

I replaced this as part of the kit, so I'm guessing something else after this has fried this part?

[Ian Paul]

Re: Vestel 17PW16-2 troubleshooting

R801 is a Varistor. Should read quite high ohms. They can break down, but I'm not so sure with the fault you are getting.
Some Varistor info:-
http://www.electronics-tutorials.ws/.../varistor.html

[vinceroger69]

Re: Vestel 17PW16-2 troubleshooting

D824 - Diode STTH12 +Insulation kit
did you fit the insulation kit? as new diode maybe shorting out on the heat sink if you didnt
i would also re check all your work ie capacitors and diodes etc fitted the correct way wrong as we have all made the odd mistake

[dskall]

Re: Vestel 17PW16-2 troubleshooting

So you indicate D800 is bad. You said you replaced it but kit is not showing as part of the kit.

[vinceroger69]

Re: Vestel 17PW16-2 troubleshooting

is d800 the bridge rectifier?

[dskall]

Re: Vestel 17PW16-2 troubleshooting

Yes Post 3 has .pdf of psu

[Shotgun25]

Re: Vestel 17PW16-2 troubleshooting

So you indicate D800 is bad. You said you replaced it but kit is not showing as part of the kit.

Hi,

Yes you are right, I've just been clearing my bench and I found the little tub of parts I removed (kept for reference until fixed) and I don't see one in there, and it looks like you've done due diligence and cross-checked my list, thanks

I thought I'd replaced it just looking at the solder joints, seems it was crappy factory soldering.

I'll look for a part and give an update when it's replaced.

Does it sound like D800 bridge rectifier was the first point of failure or should I replace the varistor (MOV?) as well?

[Shotgun25]

Re: Vestel 17PW16-2 troubleshooting

D824 - Diode STTH12 +Insulation kit
did you fit the insulation kit? as new diode maybe shorting out on the heat sink if you didnt
i would also re check all your work ie capacitors and diodes etc fitted the correct way wrong as we have all made the odd mistake

The replacement part was provided with a plastic insulating film with some thermal compound, see pic, thanks for the idea though.

Also I've checked capacitors which is easy on this board because of the thick line on the -ve side.

It's sounding like the bridge rectifier at D800 is to blame.

[Ian Paul]

Re: Vestel 17PW16-2 troubleshooting

I would guess the Varistor is not the cause of your fault.

[Shotgun25]

Re: Vestel 17PW16-2 troubleshooting

I would guess the Varistor is not the cause of your fault.

Thanks!

The bridge rectifier D800 is labeled KBL10 for reference.

[Ian Paul]

Re: Vestel 17PW16-2 troubleshooting

This:-
https://cdn.badcaps-static.com/pdfs/...645b143aa0.pdf

[Shotgun25]

Re: Vestel 17PW16-2 troubleshooting

This:-
https://cdn.badcaps-static.com/pdfs/...645b143aa0.pdf

Yeah that's the datasheet I found last night when I searched for it.

I'm going to have to buy this on ebay or amazon as I don't have a list of things to buy from Farnell or RS and I assume I'll incur shipping.

I'll check in when I have the part.

Thanks for keeping an eye out on my thread, it's been sat in my house for around 3-4 years now and I want a victory

[vinceroger69]

Re: Vestel 17PW16-2 troubleshooting

rs free shipping no minimum charge at the minute takes a few minutes to register with a credit card i use them a lot lately as good prices even when they do have a minimum order its usually £5.00 .

[Shotgun25]

Re: Vestel 17PW16-2 troubleshooting

rs free shipping no minimum charge at the minute takes a few minutes to register with a credit card i use them a lot lately as good prices even when they do have a minimum order its usually £5.00 .

Ooooh, I was just about to try and make up a £20 order on Farnell, RS it is then, many thanks for that.