Samsung TV randomly restart, UA55ES8000

[mikkele86]

hello.

I have a Samsung 55" TV model UA55ES8000.

issue:
randomly restarts.
Seems to stop restarting after 1-2 hour of ON time.

I have not taken any voltage readings yet, as I don't know what to look for.
I have attached a few pic's of the motherboard etc.

BN94-05570R
BN41-01800A

[nomoresonys]

Re: Samsung TV randomly restart, UA55ES8000

First things first: Test connector from mainboard to powerboard on powerboard side, sholud be a little legend/map of expected voltages, test with tv plugged in but off then hit power, report both conditions here, give pin number, pin description and condition on and off, demonstration in signature below.

[mikkele86]

Re: Samsung TV randomly restart, UA55ES8000

ok. got the measurements.

check out measurement.png

[nomoresonys]

Re: Samsung TV randomly restart, UA55ES8000

Ok, those look pretty good, try a factory reset if you didn't already, if that don't work try a firmware update, 2 good and free things you can start with, if that don't work will have to look deeper.

[neilc6]

Re: Samsung TV randomly restart, UA55ES8000

Try disconnecting the wifi module.

[mmartell]

Re: Samsung TV randomly restart, UA55ES8000

This might be the set that has the service bulletin on it. IIRC it was about the power connector making bad contact.

If budm sees this he can confirm or deny it.

[budm]

Re: Samsung TV randomly restart, UA55ES8000

This might be the set that has the service bulletin on it. IIRC it was about the power connector making bad contact.

If budm sees this he can confirm or deny it.

That is correct, inspect the connector at both ends. I always inspect the connector theses days with or without the service bulletin. Samsung uses crappy caps and now crappy connectors

[mikkele86]

Re: Samsung TV randomly restart, UA55ES8000

I can comfirm im running the newest firmware and did a reset, no change.
where do i locate the wifi module ? note, im using wire, so wifi is not used.

I did check the connectors, no funny color.
also did a visual inspection of the caps, nothing unusual, no bulge/residue.

Im going to try and catch my TV restarting while i probe it with my multimeter.

[mikkele86]

Re: Samsung TV randomly restart, UA55ES8000

so something interesting came up while probing around.
I started by removing the power cable between powerboard and mainboard to isolate the powerboard, turned it on, nothing happend, it kept running as it should.

reconnected everything and started probing around the mainboard.
to my surprise I found a place/power-rail where I could force restart, by just touching the pin with my probe(GND from multi-meter not touching anything).

It turns out, everytime i would touch pin 4 on IC202 it would restart.
Pin 4 is a Feedback input, see attached images

also another similar IC, IC212 would do the same, but I could here a electric "fzzzzzz" sound when touching pin 4.

what you make of that ?

[mikkele86]

Re: Samsung TV randomly restart, UA55ES8000

Pulled out the wifi module and it stopped restarting

Problem solved

[budm]

Re: Samsung TV randomly restart, UA55ES8000

Looks like Samsung needs to add the cause of the problem to their service bulletin.

[nomoresonys]

Re: Samsung TV randomly restart, UA55ES8000

So you didn't try just disconnecting the wifi module or you mean you had to remove it to get tv to work?

[mikkele86]

Re: Samsung TV randomly restart, UA55ES8000

So you didn't try just disconnecting the wifi module or you mean you had to remove it to get tv to work?

I had to remove it/unplug it.