Re: Sony bravia klv-32s200a
Thank you for the assistance.
On this occasion the bad actor is the inverter transformer.
I proved it by disassembling the panel so that I could see the CCFL's.
With this inverter board each transformer operates 2 tubes.
The suspect transformer fails to ignite one of two CCFLs in the transformer circuit.
Moving the suspect transformer to a different location on the inverter board moves the fault as indicated by the failed CCFL ignition at the new location.
If I can locate the inverter transformer...
Kevin O'Henly
Ontario Member
Last Activity: 12-16-2014, 01:09 PM
Joined: 05-05-2009
Location: Brockville, Ontario
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Sony bravia klv-32s200a
This LCD set has a CCFL inverter / panel problem.
The set powers-up with a green led set indicator.
Then the panel is backlit; stays backlit for 2 sec. and then the backlighting goes off.
...no red led error blink code???
It is my experience that when an LCD goes 'on' and 'off' like this one does the problem is a CCFL and/or inverter issue. ...almost every time.
In this case the inverter board is defective. The bad actor is the OZ9966 IC
I would also like to replace the inverter transformer T831/Y6K5 .
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Re: Sony Bravia LCD KDL-32L4000
Sorry for the long time to re-post on this thread.
I eventually fixed the power supply and since I did not have all the parts to fix this set I then sold the set for parts.
A big Thank You to all that contributed.Leave a comment:
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Re: Sony Bravia LCD KDL-32L4000
cool.
Very useful insite into the cap. substution issues.
THX, el3ctroded.
I have a home brew ESR using a scope and signal generator.
This "home brew" method requires good working caps to compare to the cap under test. This method works well and can often identify a bad cap incircuit, though it is baet to pull the cap out of the circuit for repeat testing.
...are we ready to plow into an actual defective PSU from the Sony Bravia LCD KDL-32L4000? I have standby Vdc and that's about it.Leave a comment:
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Re: Sony Bravia LCD KDL-32L4000
Cool,
...on the same page then.
Still with the power supply board...
I know that with the smaller (15 in. to 22 in. ) LCD PSUs it does not seem to matter what value of capacitor you stick back in to the PSU circuit as long as the capacitance value is higher than the one you pulled AND the replacement capacitor has a voltage equal to or higher than the one you are replacing.
For example; I have replaced a bulging 820 micro-farad capacitor @ 25V with a 1000 micro-farad capacitor @ 35V; no problems....Leave a comment:
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Re: Sony Bravia LCD KDL-32L4000
Cool,
Is it fair to say that until the PSU has been eliminated as a fault then the PSU is suspect; let's say, "Guilty until proven innocent?"?
Is it also fair to say that if a PSU has the stand-by rail up and "PS-ON" is active (high or low as the case may be for that particular design?) then a properly working PSU will come out of standby with all the rails “on”; ie. powered-up?
If all of this is fair to say then the next issue to tackle is PSU “loading”.
It has been my experience that a properly...Leave a comment:
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Re: Sony Bravia LCD KDL-32L4000
Cool link. THX.
The point about signal dynamics is also useful.
Is there a general method for fixing a set?
If so then it may go something like this?
~ PSU stand-by power available? NO - then fix/replace PSU
YES
power on the set
~PSU comes out of stand-by? NO - is "PS-ON" signal high?
YES
No picture? NO - check ribbon cables and inverter/CCFL, spend
some time with the good people at Badcaps....Leave a comment:
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Re: Sony Bravia LCD KDL-32L4000
el3ctroded & Fred,
Agreed. If one or more ccfl's fail then the inverter will fail as it is supposed to do.
Would it not be great if we could test the PSU (board-g) and CPU (board-a) without the panel inverter connected ? This would rule-out 1/2 to 3/4 of the LCD faults in one simple test.
So the question is; With a properly functioning Bravia LCD can the PSU cable to the inverter board be removed and still have the PSU come out of standby with board-a still connected?
I think so but I...Leave a comment:
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Re: Sony Bravia LCD KDL-32L4000
Thank you Wrog.
This should be fun and an interesting thread development but we will likely not have working TV's at the end of the day.
There is a link at this thread start to download a schematic for the Sony Bravia LCD KDL-32L4000 if you need it?
It would be usefull to troubleshoot any and all SMPS stand alone. Yes?
Get the PS working then load it up and see what happens electronically.
As you have a good PS perhaps could we try an experiment to determine if board-g will come out of standby...Leave a comment:
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Re: Sony Bravia LCD KDL-32L4000
Hi all.
I am back (originator of the thread) to look at restoring function to the KDL-32L4000.
The Delta EADP-170AF A SMPS is what I was interested in fixing.
Since my last post I have discovered that this SONY LCD TV has been kicked around the block before I received it. The connector between the CCFLs and inverter board was missing and while an inverter board was in the case it had nothing to do with this set. The set will need the inverter board.
Yep! ...a mess.
All that being so I still...Leave a comment:
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Rca L32hd32d
Good folks at Badcaps,
symptoms:
~ TV power-on dual-color LED shows green after red.
~ backlighting winks on and off once an stays off.
~ no bulging capa or bad caps using the ESR scope and signal generator method.
~ no sound from external signal sources or internal DVD.
~ DVD responds to panel switches: "ON" and "EJECT"
RCA has not provided the power supply connector voltages for CP3908-1 and CP3909-1. These connectors go to the control board.
Thank you for any assistance you... -
Philips TV/LCD 15PF5120 "No Signal" using DVI-I
Hi all,
I have a philips model: 15PF5120 showing a "No Signal" condition when connected to a PC using the DVI-I cable input.
No bad cap.s this time. All the electronics checked out 100%.
To understand the problem I had to understand DVI. Judging from the blog community, I am not the only one that needed some assistance in this area.
If you need a DVI primer then checkout:
[url]http://en.wikipedia.org/wiki/Digital_Visual_Interface#Overview[/url]
and:
[url]http://www.playtool.com/pages/dvicompat/dvi.html[/url]... -
Re: samsung 920N, MJ19BS inverter/power board fault
Worked for a bit then went for a s..t.
rgs,
KevinLeave a comment:
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Re: Twin Samsung 931b monitors
See picture of the cap. shorting resistor.
rgs,
Kevin...Leave a comment:
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Re: samsung 920N, MJ19BS inverter/power board fault
Repaired the hybrid (see the attached png.s)
...improved on the second try.
The component moves around as it is soldered.
A dot of crazy glue helps hold the part in place.
Works good, now.
Thanks to all that contributed....Leave a comment:
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Re: Twin Samsung 931b monitors
I discharge caps using an axial leed 1k ohm resister with insulation on the leads and a blob of solder on the lead ends. Then short the capacitor leads with this resistor, count to 10 and your done.Leave a comment:
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Re: Sony Bravia LCD KDL-32L4000
Actually, no.
With the "PS-ON" lead floating when AC power is applied then the 4VSB (4Vdc stand-by) is not generated. This is due to RL1 normally open contacts not closing. Which seems to be due to "PS-ON" being disconnected. I think?
OOps!
I just tried method one. With "PS-ON" clipped to Board-A, CN1, Pin13.
I had a probe slip and fried Q3 (2sk3568 mosfet, schematic 1of2, position A-8) so I do not have a measure of the floating voltage of the "PS-ON" lead...Last edited by Kevin O'Henly; 01-18-2010, 12:20 PM.Leave a comment:
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Re: Sony Bravia LCD KDL-32L4000
Hi PlainBill,
I like method 2 because it's easy,
With this in mind I poped pin13 out of the cable connector at Board-A, CN1, pin13 "POWER-ON". POWER-ON becomes "PS-ON" on Board-G, CN202, Pin1. The "POWER-ON" is generated by the Board-A controller IC.Leave a comment:
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Re: Twin Samsung 931b monitors
Hi,
I would recommend a grounded tip iron (3 prong cord plug) into a ground fault outlet. 60W sounds about right. Get a variety of tips.
I have no experience with butane irons.
Keep a fan blowing any fumes away from your face. I use a fume hood made from an old stove exaust hood. Works well.
If you have been handling led alloy solder then wash the hands before handling food or drink. Do not solder and snack.
Disconnect power and discharge any large capacitors before soldering....Leave a comment:
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Re: CCFL inverter boosting?
I would be interested in building a safe CCFT supply as well.
This responds to interest in finding or perhaps developing a DIY circuit for a safe and cost-effective CCFT inverter.
Perhaps this is best handled as a new post though...?
Well; the attached resources may further this discussion.
The basic.bmp circuit and framebarnew.pdf were found at: [url]http://pkrobot.freehostia.com/LCDRepair.htm[/url]
What do you think?
rgs,
KevinRe: CCFL inverter boosting?...Leave a comment:
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