Samsung le37b553

[sordids999]

hi guys

got this set today was told it keeps restarting then standby light flashes

13v are 12.9 volts
5.3v are 5.0 volts

main cap is 387 volts

main board is BN41-01258B
power supply is BN44-00262A

i have tried heating up the main and power supply with a hair dryer but cant get it to cut out

could it be the screen ?

thanks

[selldoor]

Re: Samsung le37b553

cant get it to cut out

Are you saying it is working normally? - fixed? maybe scared of someone wielding a soldering iron

[sordids999]

Re: Samsung le37b553

sorry selldoor what im saying is it sometimes switches off intermittently so i was only trying to see if it was a heat issue problem etc

[tom66]

Re: Samsung le37b553

There is an issue with some zener diodes on this set causing intermittent power off. Run it for a few hours I guess, then when (if?) it goes wrong, check the power supply voltages.

[selldoor]

Re: Samsung le37b553

One of the worst sorts of problem. Needs a good dust. I wouldnt have thought it was the screen or the inverter. If the power stays on when it goes into fail state what do the voltages do including the one on the big cap anything vary in time with the led flash and the restart?

[sordids999]

Re: Samsung le37b553

Ok strangely enough I just removed the board to inspect for any cold solder joints most of the screws where loose which holds the board on,but I leave it running until it cuts out

[sordids999]

Re: Samsung le37b553

One of the worst sorts of problem. Needs a good dust. I wouldnt have thought it was the screen or the inverter. If the power stays on when it goes into fail state what do the voltages do including the one on the big cap anything vary in time with the led flash and the restart?

only got it today so not had it fail on me yet but ill run and report back if it does

[sordids999]

Re: Samsung le37b553

update:

2 days now still working fine been running it flat out nothing
with some of the power boards screws loose could it have been a earthing problem ?

[tom66]

Re: Samsung le37b553

Do you have a variac? I have had some TVs where low mains voltage (within tolerance, but slightly low, e.g. 220V) caused issues.

[sordids999]

Re: Samsung le37b553

Do you have a variac? I have had some TVs where low mains voltage (within tolerance, but slightly low, e.g. 220V) caused issues.

no tom sorry
its strange one the guy told me it kept restarting on him but i cant find nothing wrong