Display issue with hp laptop

[Fraser Dalgleish]

Hi there,

I received a laptop for free from a friend. Her ex partner had threw it against a wall during an argument. It had cracks everywhere, including screen and was partially bent. On further investigation after a strip down, the wifi card had been ripped out so harshly that the mini pcie socket was broken in half. Not too fussed about this as I will have the laptop closed and plugged into TV by hdmi and plugged into ethernet. So I simply removed the socket and pins to prevent short circuits.

Now, I have replaced the base and glued the hinges so that I can open and close when required to switch on the laptop. Waited on a psu arriving in the post (blue tip) as battery was missing.

Psu arrives, plugged in a 11.6 inch 40 pin lcd simply to test (laptop is 15.6). All working fine with 12gb ddr3 (added my own 4gb stick) and 1tb hdd. Booted into Windows no problem.

Waited a couple of days until I had time to rescue a 15.6 from another dead laptop.

Wait for it though... Whoops I forgot to unplug the psu (schoolboy error I know). Witnessed a spark when connecting the lcd and that's when I realised. Now no display on any screen I connect and no display via hdmi either.

In the past when I have committed this atrocity of a mistake once before I simply replaced a resistor on the screen that had blown.

Now I'm stumped and I'm not electronically advanced enough when it comes to circuits etc to diagnose the fault. I am handy with a soldering iron though and with the right guidance I can get things done.

Laptop model: 15-p078sa (HP)
Intel Core i3 (4th Gen) 4030U / 1.9 GHz Processor
12GB RAM
1TB HDD
15.6" Display

Any other specifics required please ask away.

 

[Fraser Dalgleish]

So.. do you get any pic with the 11.6" test screen now? If yes, then buy another new screen. If not then I would suggest the onboard graphics / motherboard is toast.

Thanks for the reply.

Negative. No screen I have attached since has worked, including external monitor via hdmi (no Vga port present) if the motherboard is goosed I'm gonna be really gutted. Was looking forward to having something decent to stream movies through for the kids. I'm currently stuck with a core duo and 4gb Ddr2 ram on a much older laptop!

Any possible resistors that could be replaced on the motherboard before totally giving up?

I don't want to give up on such a half decent model

 

[Fraser Dalgleish]

Sorry, itty bitty component level diagnostics & repairs are not my scene.

Thanks anyway for your input.

I feel your pain, I wish it was something I could improve on personally.

I'll hope for an answer with someone a bit more geeky with this stuff than you or I!

 

[Computer Bloke]

I'll hope for an answer with someone a bit more geeky

You mean "a bit less professional", I think.

Repairs like this always come down to an economic decision; is the time and money better spent on this or on something else? In this case the computer's colourful history and the nature of the present fault (sparks are bad) would make most of us lean towards treating the thing as an organ donor and moving on.

Junk machines like this are ten a penny - just grab another one from the pile and get on with your life.

 

[Kitten Kong]

Yup, I’m leaning towards the ber side of things.

Obviously if you have the time and inclination ie this thing won’t beat me, then go for it.

But if you have jobs which are paying you decent money, write it off. And use another fresh donor.

 

[Fraser Dalgleish]

I agree with all above, however I absolutely begrudge giving up on a laptop until I know it's a complete lost cause. I'm merely trying to determine whether it's beyond my capabilities as a technician or not.

Plus the satisfaction of restoring a laptop received for nothing is something that just can't be beat! Ahhh

 

[Kitten Kong]

@Fraser Dalgleish there is a company in London called ACI (RMA Updates).

As a last resort, give them a call, and or ship the laptop off to them, and they can repair boards etc down to component level.

I have used them on a regular basis, and can really recommend them. They do literally thousands of repairs in a week.

rough guestimate of cost would be around £40.00 plus the vodka n tonic, and courier delivery / collection.

 

[Fraser Dalgleish]

@Fraser Dalgleish there is a company in London called ACI (RMA Updates).

As a last resort, give them a call, and or ship the laptop off to them, and they can repair boards etc down to component level.

I have used them on a regular basis, and can really recommend them. They do literally thousands of repairs in a week.

rough guestimate of cost would be around £40.00 plus the vodka n tonic, and courier delivery / collection.

Thanks for that recommendation buddy I will look into that definitely. Its good to hear about a company which actually has reasonable prices. I was willing to pay £40 - £50 for a board as a last resort if it was needed so that may be a more environmentally friendly option and I wouldn't have to throw a board in the bin!

Top marks for that answer thank you

 

[Larry Sabo]

Any possible resistors that could be replaced on the motherboard before totally giving up?

You could check for a blown resistor or fuse, and voltages at the LVDS connector. Here's the LVDS connector schematic for the HP 15 series.

Edit: Forgot to also point you to this YouTube video on how to restore the backlight by hacking the LCD PCB.