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Equipment Repairs => LCD TV forum => Topic started by: scooby-doo on November 24, 2011,08:07:54

Title: 42LG7000-ZA hit by power cut
Post by: scooby-doo on November 24, 2011,08:07:54

Hi

I am sure I have seen somewhere that LG's dont like Lightining or powercuts....Well Ihave this model that suffered a powercut...now all that happens is the front led lights up...it is very dim and slowly goes dimmer then brightens up again, then repeats...it is not in any sequence it just has a mind of its own.

PSU=EAY4050520


When these things have an electric surge what does it normally take out??

Cheers for any help

Title: Re: 42LG7000-ZA hit by power cut
Post by: scooby-doo on November 24, 2011,08:44:47

Update:-

I have just noticed the TV is powering up...the front LED is very dull....the volume control etc seems to be working...bleeps

All the voltages from the PSU-Main are fine as are the voltages to the inverter all perfect...just  not starting up the inverter pn is 2300KTG008A-F

Any pointers would be brill

Title: Re: 42LG7000-ZA hit by power cut
Post by: sparky on November 24, 2011,11:04:03

hi
check  psu sometimes the caps in there go faulty without
showing signs of them bulging main smoothing cap check
dave

Title: Re: 42LG7000-ZA hit by power cut
Post by: scooby-doo on November 25, 2011,12:13:35

Cheers Sparky...Ordered the caps and hopefully be here tomoz

Title: Re: 42LG7000-ZA hit by power cut
Post by: scooby-doo on November 26, 2011,09:36:18

Hi

Managed to pick up an 42lg5010 with a smashed screen it has the same psu in there fitted it same fault...Although a little different I also tried the inverter from the donor tv...The shitter being the main board is different...as is the tcon board

I have noticed with the back off the set when you start it up the tcon board illuminates a blue light..the backlights flash for a millisecond and then the tcon board goes out..

Question being if the main board has fluffed it then would it make the backlights flash then cut straight back out or would the back lights stay on but the problems be more related to connections/osd/etc etc

Thanks in advance

Title: Re: 42LG7000-ZA hit by power cut
Post by: scooby-doo on November 26, 2011,10:08:57

I have just answered my own question...I put the main board out of the donor set and hey presto the backlights come on, obviously cannot hook up the t con as it is completely different..but at least now I know the problem is in the main board somewhere