Tab 4 Screen Too Dark

[Nibbo]

Hi all, new on here but use lots of tablets so will find the site useful and hopefully can contribute too.

Nice little tricky one here...

We have a Samsung galaxy tab 4 but the screen is so dim we cannot use it.
We are unable to access the tablet as it has a pin number but the grid is not visible when the tablet boots up.
We are unable to do a factory reset because the 'erase data' option is not visible after the usual key combinations.
We can just make out the Samsung logo on boot up and can just make out the close down box when we hold down the power button.

The screen itself is OK; how do we know? Because we opened up another tablet and attached the ribbon from that device to the screen in this one and the content is rendered just fine.

Is it possible to do a factory reset without using the screen? Doubt it.
What else could be causing the screen to stay so dim?
If the brightness was set to minimum and then closed would it keep that setting after power off and back on?

Any ideas folks?

Many thanks

 

[Traveller]

Brightness settings could do this. What happens when, after totally shutting down, you hold volume down and power? Does the screen light up then? If so, follow the instructions on screen to enter recovery and from there, perform a factory reset.

 

[Nibbo]

Brightness settings could do this. What happens when, after totally shutting down, you hold volume down and power? Does the screen light up then? If so, follow the instructions on screen to enter recovery and from there, perform a factory reset.

Thanks Traveller,
Unfortunately nothing is visible. This is where I am a bit confused, I would have expected normal brightness during boot up and then the last used brightness setting to be applied when the tablet loads.
We just have a blank screen, we do feel a little vibration but no reset instructions visible.

 

[Traveller]

Then it sounds like you have a hardware issue. Not with the display, but with the motherboard. When you tested the display did you plug the display from the working unit into the motherboard of this unit and turn it on?

 

[Nibbo]

Then it sounds like you have a hardware issue. Not with the display, but with the motherboard. When you tested the display did you plug the display from the working unit into the motherboard of this unit and turn it on?

To test it we took the back off this tablet and another spare one and connected the spare ribbon to the display of the failed one.
When doing this the spare tablets display was clearly visible on the previously dim one but not the other way around.
Just to confirm, we set the brightness very low on the spare and restarted it just to see what happens and when it boots up the Samsung logo is full brightness and only goes dim after it fully loads, the tablet in question is always dim.
It is starting to look like a hardware failure bit I cant imagine what component would determine the brightness of the screen bearing in mind the screen works fine when connected to the spare.
Think it may be toast... maybe an excuse to buy the new Tab S2
Thanks

 

[Nibbo]

Then it sounds like you have a hardware issue. Not with the display, but with the motherboard. When you tested the display did you plug the display from the working unit into the motherboard of this unit and turn it on?

We just plugged it into the connection shown below and up came the display from the spare. Just tried a few random things...