Tab S2 display wont turn on after battery/LCD/USB port replacement?

[blackhawkhot]

Which ribbon cable? I've replaced the LCD flex cable. Can't see any other cables.

Any connections you did as well inspect all cables present that may have been dislodged.
Inspect mobo for FOD that may have fallen on it ie pins, paper clips.

 

[Silent Silent]

I've checked literally everything. I've replaced the LCD, LCD cable, usb port, battery, motherboard.

The only sign of life I get in this tablet is a brief split second occasional bright flash of colours on screen. The touch keys work and there is sound.

I have no idea what is wrong with this tablet but I'm determined to find out what it is.

Thanks for helping btw

 

[mustang7757]

I've checked literally everything. I've replaced the LCD, LCD cable, usb port, battery, motherboard.

The only sign of life I get in this tablet is a brief split second occasional bright flash of colours on screen. The touch keys work and there is sound.

I have no idea what is wrong with this tablet but I'm determined to find out what it is.

Thanks for helping btw

Like I mentioned look at couple YouTube tear down and then go over yours see if you missed anything

 

[blackhawkhot]

Was the LCD grounded to the mobo or other parts when fully assembled?
Or one of the other subassemblies.
You missing a ground?

 

[Silent Silent]

What do the grounds look like? Thanks

 

[blackhawkhot]

What do the grounds look like? Thanks

It depends. Could just a tab that hits another metallic surface.
Could be a wire or the ground is part of the ribbon cable (common).

V+ is the power (battery positive), ground is the battery negative connection in simple terms.
There any tear down vids for this? Probably.
They can be helpful.

Mustang 7747 could be right and the new display is defective. Did the old display work?
Try that if so and see it it fires up.

Best to work on a earth grounded ESD mat with wrist strap. In a pinch use a bare wood surface.
Either way bring the relative humidity up to 60% to help dissipate static. If it's dry you can boil water in the room to raise it.

 

[Silent Silent]

Quick update. So I ordered a new back cover brand new and it's still doing the exact same thing. Neither screen is working. How can it be that I can replace every single part in this tablet and it still doesn't work? Any idea how much it would cost to have an engineer look at the tablet just to tell me what is wrong with it? I'm determined to get it working now.

 

[blackhawkhot]

Quick update. So I ordered a new back cover brand new and it's still doing the exact same thing. Neither screen is working. How can it be that I can replace every single part in this tablet and it still doesn't work? Any idea how much it would cost to have an engineer look at the tablet just to tell me what is wrong with it? I'm determined to get it working now.

Is the power supply good?