packard bell Easynote TJ71 Black screen

[Krisee99]

Hello!

A friend of mine brought me a packard bell Easynote TJ71 laptop telling me that it won't turn on.
So first things first, I tried turning it on, CPU fan spins up, power led is on and HDD spins up, but the screen remains black. Doesn't matter what button I press, nothing happens.
So I disassembled the laptop to the core, took out the screen, checked the solder, the CPU and the cables, everything looked fine. So I turned it on and the laptop turned out to be alive.
Turned off again, then turned it on and the same black screen welcomed me.
Tried moving the cable connected to the screen and the screen itself to check if the cable was torn or not. After the 6th try, the laptop booted up properly.
The thing is if the laptop boots up, no matter how I tilted the screen or moved the cables, the picture was perfect, so I came to the conclusion that it was not the cable, but to be sure, I replaced it.
On the first day everything looked fine, the laptop turned on properly, but on the end of the day the same issue came back.
So it has to be the GPU or the MB itself.

Any ideas on what could be the problem or how to fix it?

 

[jarotech]

Hi, if you can, try an external monitor, if the picture is good on the external, then your screen or a circuit on the motherboard put out the backlight.

 

[Krisee99]

Hi, if you can, try an external monitor, if the picture is good on the external, then your screen or a circuit on the motherboard put out the backlight.

The external display doesn't work either. Except if the laptop is working fine.
So basically there is a 1/20 chance that it will boot up, but then everything is working perfectly fine.

 

[jarotech]

And if you try going into the BIOS, do you have the same problem?

 

[Krisee99]

Well, the problem is that it gives me a black screen as soon as I turn the laptop on.
Nothing works if the screen is black, doesn't matter what I press, or what I do, the only thing what works is the power button. Nothing else.

 

[jarotech]

Remove the RAM with the power off, with the adapter and battery removed, push the power button for 1 minute, and put back the RAM, just connect the adapter and boot. If you have two of them and two sockets, alternate them and one at a time.

 

[nutsnbolts]

I contacted HP with the same problem- as much help as a kick in the groin! A fix seems to be: Persevere with getting the thing running. After enough attempts, it will work eventually. Once it's running, NEVER power off completely. Just tell the computer to hibernate instead of turn off- change the power options in control panel to hibernate instead of power-off. Use the machine on mains power occasionally to keep the battery charged- if the battery runs out, you're back to square one.