Diagnosis of Luxor 32" LCD

[cakeyb]

I have a 32" Luxor tv bought from ASDA (walmart) that has developed a fault.

There is sound but no picture displayed.

Upon switching the tv on you can faintly see a display like black images for a few seconds but then the tv screen goes black.

I have replaced the inverter already but the problem persists.

The tv was left on for a while and does come to life occasionally but goes off at random and can come back.

I am looking for advice on diagnosing the problem further.

I have checked the power board and there is no obvious signs of damage to capacitors or burnt out components, the av board is like wise.

The LVDS (t-con) board has a blue light that comes on when the tv is turned on, but goes off after a few seconds.

This was the next component i was considering replacing.

The inverter that was replaced is an LG as is the LVDS pcb. I have found one fairly cheaply, so would consider giving it a shot.

Just wondering if this is a viable option as next port of call.

Thanks in advance.

[JHOFFMAN]

Re: Diagnosis of Luxor 32" LCD

Do you have 24 volts going to the inverter?

[cakeyb]

Re: Diagnosis of Luxor 32" LCD

Need to try and pick up a cheap multimeter to test further i guess.

Will try and get one at the weekend.

And can take some pictures and upload them.

[cakeyb]

Re: Diagnosis of Luxor 32" LCD

Havent been able to get out to get a multimeter yet.

Any indication from the description of the problem as to what could be causing this?

Does it seem like a power issue? Not enough power getting to components?

As I dont have any knowledge of repairing tv's, was just looking for some basic help and guidance on replacing components.

I have experience in computer/laptop repair so dont have issues changing boards etc.

[selldoor]

Re: Diagnosis of Luxor 32" LCD

Hi - it could be lots of things without a meter and pictures it is pretty impossible to guess. It could be power supply or it could just be a cold solder joint symptom comes on warms up expands joint goes off cools down joint reconnects comes on.
You need to be more specific in what you are telling us

You say
There is sound but no picture displayed.
But
Upon switching the tv on you can faintly see a display like black images for a few seconds but then the tv screen goes black.

The tv was left on for a while and does come to life occasionally but goes off at random and can come back.

What does that mean? Sound and full bright picture and how long for?
When it goes off how far off.

What does the power light do from plugging in - pressing power on- to
the initial fault stage .When in fault status can you switch it off?

[cakeyb]

Re: Diagnosis of Luxor 32" LCD

TV turns on fine. Displays faint image then screen goes black.

On occasion it will display a normal picture. It can last for 30 seconds or a few minutes then go off again.

When the picture goes off the screen is completely black no display at all but still get sound.

When plugged in power light comes on, and can switch the TV on, once on you get a blue glow from the LVDS or T-con board at the back, and a faint image on screen for a few seconds then it will go completely black.

Will try and take some pictures tonight and post them up.

[orfeous]

Re: Diagnosis of Luxor 32" LCD

Just got a question from a friend that have an old Luxor 42" LCD that he bought lile ~2003 or something..he told me that it was really expensive that days. Like ~3000 euro

The symptom that he described is that he must turn on and off on and off on and off etc several times.. then the TV turns on and runs fine. I havent seen the tv and symptom in real life. It was what he told me. Any suggestion on that? He told me that it can be wurth of investigate because it doesnt feel good to throw away that old expensive tv

Capacitor problem? powersupply problem? bad solders? im just guessing.
Going to look at further in time

[selldoor]

Re: Diagnosis of Luxor 32" LCD

The symptom that he described is that he must turn on and off on and off on and off etc several times.. then the TV turns on and runs fine.

Capacitor problem? powersupply problem? bad solders? im just guessing.
Going to look at further in time

Sounds likely perhaps start a new thread with pictures.

First thing to try would be to take the back off and warm it up gently with a hair dryer and see if it comes on quicker. - Warmer caps work better unless they are completely dried out. Start with the Power supply board.
Hopefully you will have caught it before further damage is caused.