Laptop Sreen Stuck On Low Brightness and Flickers when I try to Adjust it

[oasha99]

My Laptop(Dell Inspiron 15 7559) is stuck on low Brightness. Very dim screen but the laptop is still in a usable shape. This happened after I replaced a fault LCD cable on the laptop because it used to Flicker every time I moved the screen.

Before I replaced LCD cable:

- Screen worked on any brightness
- screen would flicker every time I move the screen or it would go black completely
- everything else was normal

After I replaced the LCD Cable:

- Screen stuck on very low brightness and flickers when I try to adjust brightness myself(FN keys or change power plan)
- The screen instantly becomes almost black when I remove AC power source. You can barely read from it(almost like a broken inverter but screen doesn't even have an inverter).-
- Its not a driver issue I tried uninstalling all drivers and even did a factory reset to the computer.

I think this is a power issue but I have no idea where the problem is. I didn't do anything crazy when repairing the laptop plus the new cable works. Do I just order a new LCD screen and will it solve my problem? Not enough power is reaching the back Light so Im not sure if the problem is with the screen itself. I'm writing this from my laptop but staring at a dim screen **bleep**.





Your help is greatly appreciated and thanks in advance

 

[webworkings]

Sounds like the cable either isn't the right one, there is a fault in the new cable, or the connections are not correct. First try disconnecting and then reconnecting the cable (both ends) and see if that resolves it.

If not, then I would make sure that it is actually the right cable for that device.

 

[oasha99]

Sounds like the cable either isn't the right one, there is a fault in the new cable, or the connections are not correct. First try disconnecting and then reconnecting the cable (both ends) and see if that resolves it.

If not, then I would make sure that it is actually the right cable for that device.

Hi, OP here

Im pretty sure the cable is the right one(I ordered it from parts people with the right model name) but I reverted back to the old cable and the issue still persisted. Im pretty sure the issue isnt with the cable but I'll switch back to the old one again tonight and see how it goes.

Here are the things I tried meanwhile:

• 
  I tried to uninstall/delete drivers and reinstall
  I factory reset the computer
  I tried adjusting the brightness with BIOS FN keys

Nothing so far worked, key observations are: that if I change brightness the screen flickers and if I remove the AC power source the screen almost becomes unreadable faint. If I tinker with some drivers it makes the screen act a little differently(a little brighter or starts flickering). I dont mind getting a new LCD screen but I want to be 100% sure the screen is the problem.

 

[webworkings]

I understand. Who wants to spend the money if they don't have to. You could try attaching an external monitor and see if it shows well on that. This will help you narrow things down. I am pretty sure it will show fine, as this doesn't seem like a GPU problem, but can't hurt to check.

The fact of it acting differently depending on the power source makes me think you may also want to try the following and see if it helps at all.

Try this...

1. Go into "Control Panel" and then "Power Options".

2. Click the "Change plan settings" link next to which ever plan you are currently using and then click "Change advance power settings".

3. In this new window click "Display" to open up the listings under it.

4. Now locate and click each of the following..."Display brightness", "Dimmed display brightness" and "Enable adaptive brightness".

5. Change each of these to the settings you wish, then click the "Apply" button and finally the "OK" button.

 

[oasha99]

I understand. Who wants to spend the money if they don't have to. You could try attaching an external monitor and see if it shows well on that. This will help you narrow things down. I am pretty sure it will show fine, as this doesn't seem like a GPU problem, but can't hurt to check.

The fact of it acting differently depending on the power source makes me think you may also want to try the following and see if it helps at all.

Try this...

1. Go into "Control Panel" and then "Power Options".

2. Click the "Change plan settings" link next to which ever plan you are currently using and then click "Change advance power settings".

3. In this new window click "Display" to open up the listings under it.

4. Now locate and click each of the following..."Display brightness", "Dimmed display brightness" and "Enable adaptive brightness".

5. Change each of these to the settings you wish, then click the "Apply" button and finally the "OK" button.

Hi, I've tried that but it didn't make a difference sadly. Also If I try to change the brightness by selecting a different power plan the screen will flicker the same way it flickers if I change brightness using the FN keys. Seems like every time the amount of power going to the screen changes it starts flickering.

I don't have a monitor on me or a TV(College student), as soon as I get my hands on one I'll test that possibility. However, ordering a new LCD is cheaper than getting a new monitor.

 

[webworkings]

Well I wouldn't buy a monitor. But perhaps there is someone who can loan you one for the testing.

 

[oasha99]

Well I wouldn't buy a monitor. But perhaps there is someone who can loan you one for the testing.

I'm planning on trying this out on campus computers.

So if I were to test this out on a monitor and I got a bright screen from the monitor I take it this mean its a hardware issue?

If I got the same dim screen its either the cable or a software Issue right?

 

[webworkings]

Well, if it doesn't show up on the external one, then I would be looking at either the attached cable or the attached display as the problem.

If it does show up on the external monitor as well, then I would be looking at it being a GPU problem.

 

[ductien999]

My Dell 7559 had exactly the same problem. I replaced the LCD cable, problem is not solved. I replaced the LCD screen, still low brightness but not flicker (. 15$ cable and 70$ screen for nothing. I went to the computer shop, they asked me 200$. Now I use my laptop with an external monitor via HDMI.