Announcement

**budm** · 03-16-2012, 12:52 PM

Re: VESTEL 3208 Sound but no picture

Please remember that we are trying to troubleshoot the problem from long distant, so PLEASE post good clear and well focused pictures of the whole rear view of the TV so we can see how all the boards are connected together, then good pictures of the power supply board of both top and bottom sides, closed up pictures of the power supply board connectors so we can see any lebelling on them so we can tell you which pin to use for checking the voltages. Look at the boards to see if they have any signs of bad caps with bulging tops.
Please use advanced reply to attach the pictures.

**tom66** · 03-16-2012, 04:39 PM

Re: VESTEL 3208 Sound but no picture

There are two causes of this problem:

1.) 17PW15-8 problem - the most common as this is one of the worst offenders. Absolutely rubbish power supply!

2.) Inverter problem.

You can verify which by testing the 24V output - if it's the PSU it will measure somewhere around 10-20V - too low for proper function. If it does measure 24V, it's probably the inverter.

**s_henya** · 03-17-2012, 06:54 AM

Re: VESTEL 3208 Sound but no picture

Hey tom and budm, thanks for answering,
I will load later a few pics, and wolud most appriciate
some voltage testing points,
This is the first lcd tv im repairing, all i did this far is 6 lcd monitors, and replaced 2 faulty lcd laptop screens, so im not that known to voltage testing, but more than willing to learn and try.
By the way need your oppinion about buying an esr meter, heard that blue esr meter is good, what would you suggest.

**tom66** · 03-17-2012, 10:49 AM

Re: VESTEL 3208 Sound but no picture

Originally posted by s_henya View Post

Hey tom and budm, thanks for answering,
I will load later a few pics, and wolud most appriciate
some voltage testing points,
This is the first lcd tv im repairing, all i did this far is 6 lcd monitors, and replaced 2 faulty lcd laptop screens, so im not that known to voltage testing, but more than willing to learn and try.
By the way need your oppinion about buying an esr meter, heard that blue esr meter is good, what would you suggest.

Do you have a multimeter?

For the moment, you don't need an ESR meter, but I have the Atlas ESR60 and would recommend it. It's about £70.

**s_henya** · 03-17-2012, 05:12 PM

Re: VESTEL 3208 Sound but no picture

i've uploaded some pics, i hope it will do,
if its not that clear i can try my girlfreind's iphone camera.

i need to share some new discoveries,
before giving the tv to me, my freind took it to someone, who hasn't been able to repair it, and i dont know what he did. :-(.

new problem appeared when i wanted to do the flashlight test,
the tv stanby led was flashing in red colour, and there is some strage noise, i think i comes from the power supply pcb,

asking my freind if it happend to him also, he said that the tv had no pic whith sound or this situation alternately.

another strange thing i found is that are two diods missing in the power supply. their legs are cut from the upper side of the pcb,
note sure if the seller did that or the former repairman.
its D840, D841.

Please guide me :-)

Attached Files

**s_henya** · 03-17-2012, 05:42 PM

Re: VESTEL 3208 Sound but no picture

a few power on and off and its on again, but still no picture, but have sound.

**s_henya** · 03-21-2012, 03:13 AM

Re: VESTEL 3208 Sound but no picture

hey guys, any ideas or test points, i really need your help!

**multimeter** · 03-21-2012, 07:50 AM

Re: VESTEL 3208 Sound but no picture

check voltages coming out of the power supply with reference to you pdf schematic,you will notice that some of the connectors are missing on the schematic,,write down the voltages from your pdf linked to the connectors on your board,mark it on paper ,on these supplys there are no markings for voltages printed on the board,then reference to what the voltages coming out actually are,im guessing your missing a 24v rail to the inverter,if you are ,esr the output capacitors out of circuit,take it from there then

**multimeter** · 03-21-2012, 07:51 AM

Re: VESTEL 3208 Sound but no picture

p.s the output caps on these supplys do fail without bulging/leaking

**s_henya** · 03-21-2012, 04:46 PM

Re: VESTEL 3208 Sound but no picture

thanks multimeter, i really appreciate the help,

i will test the voltages on the inverter connector pins,

and update tommorow,

i should be getting 24vdc right?

your theory about the caps, sounds reasonable but what would you suggest,

try reccaping the whole power supply pcb?

as i said im currently serching for an ESR meter,

but can's seem to find someone on EBAY who is willing to ship to Israel.

iv'e saw a post cant remember where, that there are 2 15nf gray rectangular caps that could be faulty, upper left side of the pcb,
you are able only to see the side of the cap in the picture,
there is another one on the right lower side.

do you have any expirience in checking those caps,

**multimeter** · 03-21-2012, 05:07 PM

Re: VESTEL 3208 Sound but no picture

Originally posted by s_henya View Post

thanks multimeter, i really appreciate the help,

i will test the voltages on the inverter connector pins,

and update tommorow,

i should be getting 24vdc right?

your theory about the caps, sounds reasonable but what would you suggest,

try reccaping the whole power supply pcb?

as i said im currently serching for an ESR meter,

but can's seem to find someone on EBAY who is willing to ship to Israel.

iv'e saw a post cant remember where, that there are 2 15nf gray rectangular caps that could be faulty, upper left side of the pcb,
you are able only to see the side of the cap in the picture,
there is another one on the right lower side.

do you have any expirience in checking those caps,

if i remember rightly it is 24v,but i cant remember,it could be a 33v rail,but the schematic will tell you,as for replacing the caps,i tend to track down the faulty ones,replace those,then if that works il recap the supply totally with panasonic fc/fm series,most of the caps in your vestel supply will be gp caps,so fc series is a good choice,as for the 15nf caps,most multimeters may not be able to go to the lengths of those caps,generally they go short,an insulation test will give a good indication of that,check your voltage outputs first.

**multimeter** · 03-21-2012, 05:10 PM

Re: VESTEL 3208 Sound but no picture

oh,and double check on dry joints on the underside ,they are notorious on vestel!,i found 14 cracked joints on the very supply you have.

**budm** · 03-21-2012, 07:14 PM

Re: VESTEL 3208 Sound but no picture

I looked at the SCH (17pw15-8), since you indicted that you do get sound but no pictures, it means that the 12vdc is working which means PS_ON is working OK and so as the PFC Voltage boost circuits, so you should have the 24vdc at the PL801 PIN 1~5.
Also look at the BL_ON PIN 12 of PL802, what do you have there?
Also any pictures of the inverter board, do you get 24vdc at the inverter board power connectors?

**s_henya** · 03-24-2012, 03:45 PM

Re: VESTEL 3208 Sound but no picture

hey guys, sorry for delay,

so i did some more testing,

when i disassembled the inverterboard i noticed there is a lamp missing,
added a picture, and saw some burn marks on some of the lamp connectors on the inverterboard.
i really dont know if its normal or not, you tell me.

when i assembled the inverter back, i saw that few of the lamps where not sitting staight moved them a little and turn on the tv, i got a white light for a sec on the upper side of the screen, where touched the lamps, no picture though. when flashed with a bulb got no picture (maybe doing it wrong)

is there any way of testing the inverter?
from my expirience from monitors, the lamp came with a 2 pin connector,
that i could plug a test lamp to, in this inverter the lamp is connected with only one pin staight to the inverter.
how is it working with one side only anyway??
(maybe the otherside is connected to somewhere, don't know where)
by the way checked both fuses on the inverter and turned OK.
got nothing connected to CN14- is it ok?

PL802/G800 Conector on the power supply pbc goes to the inverterboard,
pin 1 (red) +24.5vdc
pin 2 (red) +24.5vdc
pin 3 (red) +24.5vdc
pin 4 (red) +24.5vdc
pin 5 (red) +24.5vdc
pin 6 (black) (-)
pin 7 (black) (-)
pin 8 (black) (-)
pin 9 (nc)
pin 10 (nc)
pin 11 (yellow) +21.8vdc
pin 12 (blue) +21.4vdc

PL801: (goes to the speakers pcb)
pin1 (nc)
pin2 (nc)
pin3 (nc)
pin4 (red) +24.5vdc
pin5 (red) +24.5vdc
pin6 (black) (-)
pin7 (black) (-)
pin8 (nc)
pin9 (nc)
pin10 (nc)

what should i test next?

im thinking of buying the peak esr70 so i can do a little more testing of the caps. (need it anyway when repairing computer main boards and power supplys) its too expensive for me, waiting for a nice deal, can't pay more than 140$ including shipment to israel.

**shepp** · 03-24-2012, 06:22 PM

Re: VESTEL 3208 Sound but no picture

some tvs have a protection function on the screen, so if one of the transformers on the invertor board is dicky the rest wont work and the screen wont come on, you can test the coils on the transformers using an ohm setting and measure across each set of windings check all transformers and then see which ones are differant if any to the rest, this will rule out the invertor board but i would suspect a transformer is dud, i did this and found 2 transformers out of 8 dud, they were about £14 each so i decided on a new invertor board and paid £24, hope this helps (im a new bee to the site)

**s_henya** · 03-25-2012, 01:47 AM

Re: VESTEL 3208 Sound but no picture

can anyone explain how to check the inverter transformers?
using a multimeter,
should i take the out or in circuit,
how would i know which is primary, and secondary,
what resistance should i expect?

**multimeter** · 03-25-2012, 04:19 AM

Re: VESTEL 3208 Sound but no picture

Originally posted by s_henya View Post

can anyone explain how to check the inverter transformers?
using a multimeter,
should i take the out or in circuit,
how would i know which is primary, and secondary,
what resistance should i expect?

you need to replace the lamp first,if one is missing it will cause 2 seconds to black,im guessing your transformers are ok,without the lamp you may be wasting your time,if you have spare ccfls with the right connectors then you can plug them right into the inverter board,if all light which i think they will ,then your inverter is fine,lamp first ,testing transformers later.

**multimeter** · 03-25-2012, 04:29 AM

Re: VESTEL 3208 Sound but no picture

s there any way of testing the inverter?
from my expirience from monitors, the lamp came with a 2 pin connector,
that i could plug a test lamp to, in this inverter the lamp is connected with only one pin staight to the inverter.

the other end of the tubes would be connected to ground,thats why you only have one wire that you can see,makes it a little harder to just replace with spare tubes for testing purposes

**shepp** · 03-25-2012, 07:39 AM

Re: VESTEL 3208 Sound but no picture

Un plug the tv, leave it for a bit say 10mins, then remove the plugs from the invertor board(all the plugs inc lamps), set your meter to ohms and measure the resistance on the coils of the transformers, if any are higher than the others these are likely to be bad or vice verser, remember these are high voltage so do not do this with the power on!

Announcement

VESTEL 3208 Sound but no picture

VESTEL 3208 Sound but no picture

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment

Comment