Samsung UN78JU7500FXZA 8 blinking light code

[baleman2]

For the first time in 4 years I unplugged my Samsung TV last evening to plug in a ROKU.
TV is wall mounted. To clean up some loose hanging cables, I slid my TV about 8 inches to the left of its original position in order to give me a bit more space. My wall mount allows for this.
I unplugged the TV from the wall outlet before doing this. I mounted my Dish TV box to the wall, my Samsung "oneconnect" to the wall, and used some plastic wire ties to bundle up my loose cables. Everything was plugged back in as before to the "oneconnect", Dish TV box, etc.
After plugging the TV back in to the wall outlet, the TV will not power on. The red light is on at the bottom right of the TV. A push on either my Dish TV remote power button or my Samsung Smart Hub power button produces the following blinking light sequence:
1) Solid red light after plugging in to the wall outlet.
2) Pushing the power button on the remotes causes 2 rapid blinks of the red light for 4 successions, i.e., a total of 8 blinks.
3) Solid red light after the 8 total blinks.
I've taken the TV down and removed the back panel so that I can look at all the boards, but am unaware of any testing that I should attempt.
I have no problem working with electronics. I'm an IT manager and am accustomed to complete computer repair/rebuilds/board replacements.
I'm hoping someone can help me avoid the cost of a serviceman's repair.
Please advise

[budm]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Lets start by uploading good clear pictures of the whole backside of the TV showing all the boards so we can see what we are dealing with.

[nomoresonys]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Start with simple reset, unplug tv hold in power button for 30 seconds release, plug tv back in and try it, leave all other devices unplugged dvd player etc. til you get the tv going.

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Am uploading an overall view of the back of the TV. Also, individual pics of the different boards.
TO nomoresonys: I've spent the last several hours using the "standard" reset processes, i.e., all the ones that I could find on GOOGLE.
PICTURES TO FOLLOW.

[nomoresonys]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Ok, check your voltages #3 below, try to do it just as instructed.

[nomoresonys]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Should also be able to test powerboard and backlights, with tv unplugged from power, unhook cable from powerboard to mainboard, leave it unhooked, plug power cord into powerboard, see if backlights come on and stay on.

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Guys:
My computer shows the pictures have been uploaded, but I don't see them yet.

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Hopefully, pictures attached.

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

To: nomoresonys
Last picture of main motherboard is getting uploaded now.
I've watched the videos attached to your post relative to testing. I have no problems determining different boards on a computer; but, I'm a novice when it comes to the boards shown in these pictures.
Can you highlight one of these pictures so I'll know what to test?

[nomoresonys]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Pictures are a little blurry looks like connector CNM803 on the powerboard which you have pictured there is the one you want to test, see the legend/map for expected voltages?

[nomoresonys]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Be VERY CAREFUL what you touch on the HOT/DEADLY side of the powerboard, that connector is on the cold side.

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

I don't want to make any mistakes here, either. I'm going to send better pics of these connectors.
This is CN9003 - at top left of Power Board. I seen no voltages in the legend associated with it.
More Pics to come.

[nomoresonys]

Re: Samsung UN78JU7500FXZA 8 blinking light code

That's not the one were wanting to test first.

[nomoresonys]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Is there a CNM803 on your board?

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

This is CNM803 - at top left of Power Board just under CN9003.
I see no legend of any kind associated with it.

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

This is CNL802A - at top right of Power Board. Legend is there, but now what I would expect to see for voltage readings????

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

This is CNL802B - located just under CNL802A. Again, legend is there but not what I'd expect to see for voltage readings.

[nomoresonys]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Find CM891 typical round capacitor, the legend/map should be next to it.

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

I've only found one labeled CA851 and am sending pic of it. I'll keep looking.

[baleman2]

Re: Samsung UN78JU7500FXZA 8 blinking light code

Found it - pic to follow. Don't give up on me.