LG 80FR LCD- mainboard gone bad

[avink]

My screen went black and LG folks tell me that its mainborad has gone bad. the only option is to replace the board..and the cost is around 11k..It has been just about 1.5 years since I bought it. He tell me that its because of power fluctuations. So my Q is :

1. shouldn't it have a built in spike/surge protector ?
2. Does anyone know if the mainboard can be repaired?

 

[adder]

Well none of the tvs i know are designed to operate more then 110 to 240v.In india volages of 250+ are quite common,its highly recommended to get a stabilizer like the V-guard digi series .
In bangalore in the night one can at times see voltages as high as 300v.

Repairing the board are gone with the CRT days.

 

[NetFreak]

My screen went black and LG folks tell me that its mainborad has gone bad. the only option is to replace the board

Get some non-authorized shop to check the TV as well.

Sometimes it is as simple as capacitors in Power Supply that are gone but they insist on replacing the whole supply.

Do you see power LED's blinking when you turn on the TV? If yes, how many times? This tells the error code and points to what might have failed.

Do you hear sound?

 

[theironhorse]

try to get it checked at a private electronic repair shop.. it might be just the input board fried that can be repaired.. or might be just few fried circuits..

 

[Kittu]

Do follow the above suggestion and get a stabilizer for the TV. Use the surge to mains wall - and Stabilizer to Surge - TV to Stabilizer .. You are insured ...

 

[csczero]

how about a UPS ?. I have 800va UPS would that be sufficient or it still requires stabilizer ?

 

[avink]

Finally got it repaired through a local repair shop. This guy had an independent service center/agency. turned out that it was the inverter board rather than main board the LG folks were saying. It cost me 6K.

First thing I did after fixing it, was to get a Vguard Crystal stabilizer and hook my setup to it...learnt it the hard way . The crystal is 2 Amp capacity. I will be hooking my 32" LCD+Denon1610 +TataSky/Xtreamer Pro to it. I was confused between crystal and Digi 100(3Amp). Crystal looked sleeker and is wall mountable. Though the Vgaurad guy has promised to change it incase I require more power and change my mind. He mentioned that incase of overload it would cutoff and I should know that I need higher capacity stabilizer.

1) is that true. In others words if its not cutting off, should i assume its supporting my needs(sounded like a dumb Q as I was typing ..but i thought i will still confirm it with the experts

_Thanks

 

[avink]

Sadly, within six months of changing inverter board, now the screen is gone again. It only plays audio .no video. The repair guy is saying it could be mainboard this time and worse still the main panel (~ 20k) . I am really annoyed with the quality of this LCD ..its not been 3 years yet and i have already spent so much on it.

 

[CANDUU]

Sad to hear it,this time pls dont try to repair ,buy a new tv with maximum warrenty...

 

[sudhishkv]

Do the servicing by yourself. Your main board is just fine otherwise it may not have worked when you got it serviced. Mostly some of the capacitors or transistors must have gone bad. Also check for the open resistors.

Tools you needs

1) Screw driver to remove the screws
2) Soldering Iron
3) Desoldering Iron(With heating element)
4) Multimeter(You will get a good one for Rs. 200)
5) Soldering Flux
6) Soldering Lead

You need to learn how to find the fault in following components

1) Capacitor
2) Resistor
3) Transistor(PNP and NPN)
4) Diods
5) Finally, check for the dry solder joints.


Also watch this video
YouTube - ‪Broken LG LCD TV Capacitor‬‏

 

[CANDUU]

luck favours the brave,anyway it is broken why not give it a try as sudhishkv mentioned......

 

[ark]

luck favours the brave,anyway it is broken why not give it a try as sudhishkv mentioned......

A word of caution though. You will be dealing with high voltages , need to take necessary precautions.

It needs some skills to de-solder stuff from a multilayer pcb. Also there is high possibility of damaging the tracks. It gets more complicated if there are SMD components.

 

[avink]

thanks for the suggestions guys. I got it repaired through a local vendor.couldnt gather the confidence to try it out myself ..it was the mainboard ..costed me around 8k

 

[ark]

thanks for the suggestions guys. I got it repaired through a local vendor.couldnt gather the confidence to try it out myself ..it was the mainboard ..costed me around 8k

Hope it gives you trouble free operation now. Did he replace the board or repair it ? If it was repaired, what had gone bad?

 

[avink]

he changed the main board.

 

[avidyarthy]

You should'nt blame LG for this ... looks to be the only high voltage prior to the initial failure. Some components take their own time to conk off once fed with undesirable power.

ehehe ... Noida, eh? Place known for high fluctuations ..! How did your TV survive the 1.5 years without a stabilizer????????????? LG is surely giving top quality stuff!!!!!!!!!!!

 

[avink]

Some components take their own time to conk off once fed with undesirable power.

This is interesting..I hope there is not more to come