Hp probook 470 g1 starts fine but nothing on my screen, works on my tv but not laptop. only a week old have I done something

SOURCE: Display Failure for HP dv9000 Laptop 17"

Thanks Zohail for your comment.
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My friend Juan Carlos asked me to check his laptop.
Captioned laptop was checked/inspected by two technicians and no one get it to work.
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Fault Description.

After 3 months of use. The wireless mini-card fails. No wireless connection can be made.
Randomly the laptop fails to boot up. Black screen and power led (blue lights) on.
Owner took out the battery module and reset the laptop according user manual instructions. He got it to work a couple of times until the laptop was un-responsive at all.

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I goggle the Laptop model number and the fault description and plenty entries showed up. Faulty motherboard, short guarantee from HP, etc…
I found the service manual from this series and I decided to verify if the motherboard was really damaged.
Prior a full dismantling I reset the bios by disconnecting the CRT battery. I made an other test: the machine starts the boot sequence, read from DVD, later pass to hard drive, the hard drive led blinks a couple the times and that’s all. After a period of time the laptop shut downs itself and reboots again….black screen ….nothing……..
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I tear down the laptop (according service manual instructions), check all boards and I did not find any sign of damaged component or over-heating.
I took special care during the dismantling, I let the CRT battery in place (motherboard) but I disconnect every thing. Everybody must be aware that this particular mobo has a
small switch (identical to the power switch). Captioned switch can no be accessed from outside (you have to dismantle the computer in order to see it). I took a ball pen and press this switch for five seconds (twice). I assembled back the laptop and make a test in order to see if starts. The machine boots and the set up screen came up. “ Press F1 to continue… I press F1 and the start sequence complete….
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I found that the power settings in Power Profile (HP Recommended) was 2% in critical battery (too low in my opinion)
Conclusion: the machine is working; the only thing that I could not get to work was the wireless min-card. I reload the drivers but probably the mini-card is faulty.

I hope that this solution helps.

Posted by MCampos

SOURCE: hp laptop 9720us screen wont brighten or dim. last

You got the wrong inverter fitted - i'm sure your unit requires a sinle lamp inverter and they have cheated - putting in a generic lamp inverter and branching togeather the wires to accomodate the single plug thus reducing the available volatage for the lamps - this is why it's dim - correct part is 431391-001 Display panel power inverter - For use with single lamp display panel

SOURCE: Hp 4510s probook will not power on

Your battery is shot.

SOURCE: hp probook 4510s cannot get cd tray open

Maryar,
The tray may have got stuck. It happens. What you can do is look for a small hole on the face of the drive, either on the tray front or just below it. Insert a paper pin through it. The pin will press a lever which will open the tray. If you do it a few times the tray may get unstuck finally. Hopefully.

SOURCE: i can adjust screen brightness

Typically there are two ways: through the keyboard, usually a function button and brighter or darker button, and 2nd in the power settings. Lower screen brightness gives much longer battery life.