Laptop screen doesn't light up

Fatty-McPhat

Hey, I've got a HP DV6700 series (6768se) laptop, and recently my backlight has crapped out on me, I think. I'm not really sure what's the problem, that's why I'm here. When I start up the laptop, the backlight will flicker on for 1 second, then it goes off and doesn't come back on again. I can barely see what's on the screen, can see best under light, and I can connect to a monitor/TV through HDMI fine, so it's definitely not a problem with video card or anything. I have bought a new inverter, and still have the same problem. I also disconnected and reconnected the LCD cable on the back of the screen. One thing I did find out, if I take out the left connection to the inverter (pictured), and put it back in, the screen will brighten up back to normal for a second. I've also had the screen brighten up when I pinch the LCD cable where it's going into the laptop to connect to the mother board.

So, anyone have any idea what I can try, or what the problem could be? Thanks.

Dunadan019

the backlight is just a flourescent light bulb.

like any light bulb, they eventually go bad.

you need to replace it really which I have done myself on my old laptop and don't recommend. It'll probably cost you a pretty penny to get it repaired at a shop.

PirateJon

He's right, but some laptops are easier to get inside than others. I'd take a look at the manual (probably on CD or from HP's site) and see if it's hard. You can also get a quote from the manufacturer for replacing the bulb. Shouldn't be more than a few hundred.

I'd advise against taking it to the local "some guy". Way too easy to break something expensive.

I've also had the screen brighten up when I pinch the LCD cable where it's going into the laptop to connect to the mother board.

Could be a bad connector on the motherboard, bad cable, etc.

Fatty-McPhat

Yeah, I've checked with HP and it's like $400 for them to repair it (out of warranty). I'm not sure about the backlight being blown, because like I said the screen will flicker on to regular brightness sometimes.

Newton

They're charging $400 because they're going to replace the entire display. Most laptop displays aren't built to have a replaceable backlight. At least not one that can be done easily. You typically have to take the entire display apart to get the bulb out.

Anyways, it sounds more like the connector is the problem than the bulb itself. I don't know how much you want to go digging around in your laptop, but you might want to see if you can get to where that cable connects to the motherboard and check it there. Not sure if you would be able to fix a bad connector without replacing the whole motherboard, though. If that is the problem, you might be able to goop in some RTV to hold the cable in place so you get a better connection.

darkmayo

Well here is the service and maintenance guide for your model

http://h10032.www1.hp.com/ctg/Manual/c01295877.pdf

From the look of it you might be boned. That series doesnt seem to have an "easily" removable or removeable at all display cable, nor do I see a separate part number for the display cable, and the cable kit lacks the cable as well.

If you want to dismantle the unit follow the service and maintenance guide instructions (HP laptops usually have the same path when it comes to dismantling (keyboard first, then LED/Power board, then display)

Once the display is off then its easier to dismantle the display entirely so you can see if any cables are loose (tho the pictue in the manual makes it look like the display cable goes inside the display itself making it unaccessable)