Samsung Galaxy Tab 3 7.0 tablet - hard bricked?

[retiredcaps]

I bought a non working Samsung Galaxy Tab 3 7.0 tablet in hopes of fixing it.

Specs at

http://www.gsmarena.com/samsung_galaxy_tab_3_7_0-5422.php

Symptoms

- no display on screen
- nothing ever shows up on the screen (no text or android symbol/robot)
- no sound
- backlight is on and stays on
- draws about 0.9A when plugged into AC adapter
- not recognized as a USB device in Windows or Linux

What I have done so far

- hard reset (holding power on/off and volume button) does not change behaviour
- have removed and reconnected the battery (left it out for several hours)
- removed and reseated all cables

My guess is that is "hard bricked" and requires some sort of jtag programming? If yes, I have no such tools.  Anyone else see this or have other ideas?

[Kennylxix]

My first suggestion is to take the back cover off and remove the battery.   Replace and try again.

[retiredcaps]

My first suggestion is to take the back cover off and remove the battery.   Replace and try again.

Thanks for the suggestion.  Tried that as well, but forgot to mention initially.

[imidis]

Hmm, only other thing I can think of - have you tried to see if it will go to download mode? Not sure what button combo it is on that device. Though, the back light always being on is troubling. Hmm, I'd check and see what kind of voltages its reading. Sounds like somethings kicked the bucket. Though could be hard bricked. Hmm. I'm not much help am i? >.>

Oh, did you try re-seating the display cable?

[Kennylxix]

Have you tired holding both volume up and down while powering up?

[retiredcaps]

Hmm, only other thing I can think of - have you tried to see if it will go to download mode?

I have been trying with various button combinations to get it into download mode.  However, Windows and Linux on different computers cannot see the tablet as an usb device.

Hmm. I'm not much help am i? >.>

Thank you for taking the time to read and reply with suggestions.

Oh, did you try re-seating the display cable?

Did that and no change.  I have reseated all the cables, but again forgot to mention that in my initial reply.

[retiredcaps]

Have you tired holding both volume up and down while powering up?

Yes, I tried all button combinations, but tried again just now in case I missed your suggestion above and no change.  All I get is the backlight on with no text or sound during bootup.

[retiredcaps]

Hmm, I'd check and see what kind of voltages its reading.

I have not checked any voltages because the components on the pcb are an order of magnitude smaller than what I'm used to.  Unless I get my sharpest probes out, the chance of slippage and causing a short is very high.  Even then, there is still a good chance of slippage.

Now that I have seen how small these components are first hand, this will be my first and last attempt at buying broken tablets for repair.  Unless I get one for free, I don't have the equipment or eyesight to fix these tiny components.

[PA0PBZ]

So you can switch the backlight on and off with a short press of the power button?

Did you try holding the power button longer, like 30 seconds or more, when the backlight is on and off? I think my Tab3 once showed the same (backlight on and nothing else) and I 'fixed' it by holding the power button a lot longer.

[retiredcaps]

So you can switch the backlight on and off with a short press of the power button?

Thanks for replying.  If I short/quick press the power the backlight does not go on and off.  The backlight just stays on.

Did you try holding the power button longer, like 30 seconds or more, when the backlight is on and off?

If I hold the power button for more than 30 seconds, the backlight stays on and doesn't go off.

While trying all these button combinations, I had the usb cable hooked up to my computer to see if the OS sees it as an usb device and it does not.