DV9700 Backlight works for 2 sec, then goes out?

Hi everyone,

I am having some strange problems with the backlight on my dv9700...I started a thread about this maybe 2 months ago but the backlight for whatever reason started working again and I didn't have too many issues with it until recently. Lately the backlight has only been working when it is plugged in...If I unplug it but leave the lid open it still works but as soon as I close the lid and open it again its out until I plug it back in and open and close the lid. Now I can't get the backlight to work at all except it lights up for 2 seconds or so upon closing and opening the lid. I removed the display bezel to access the display inverter and check for any loose or damaged connectors but they all appear to be fine...unplugging and plugging the display panel cable connector back in also causes the backlight to work for 2 seconds and then go out again. Besides the backlight issue the laptop seems to be working perfectly fine...can anyone help me figure this out? I should mention that I upgraded this laptop to Windows 7 right away when it was released.

Thanks

Dan

 

Its your inverter

 

Thanks Jay, thats what I suspected but wanted to get an opinion on here first. It appears that my notebook would require the dual lamp inverter? Looks like prices on this are around $50 for a dual lamp inverter, is that what I should expect to pay?

Thanks

Dan

 

Well I replaced the inverter but still have the exact same problem, the backlight works for about 2 seconds after plugging the inverter in then goes out every time Where should I start looking further for problems?

Thanks

Dan

 

Bad CCFL? Replacing those is a bit of a pain and requires a little soldering. Your symptoms are unusual though.

 

brianstretch,

Where might I find information on how to replace a CCFL, and what exactly is it? I feel I have the technical knowledge and soldering skills to do it if there is a guide of some sort available anywhere.

Am I correct to assume that my problem probably isn't related to the infamous faulty Nvidia GPU issue that everyone seems to run into with this notebook model? Like I said everything besides the backlight is functioning correctly, it seems like if I were a victim of the Nvidia issue my laptop would have stopped working all together a long time ago (I have the GeForce 8600M GS.) The fact that I already had to get the screen replaced once makes me wonder though...

Thanks!

Dan

 

Might be a screen problem... doesn't look like a dead GPU problem... u might have to replace the LCD again but i would save the time and trouble and get a new laptop.

 

Yeah if it comes down to replacing the entire screen again I think I'll just hook it up to an external monitor so I can get some use out of it as a desktop instead. Might be time to start shopping for my next laptop, certainly won't be HP again...a $1300 laptop rendered useless in less than 2 years AWESOME I did some research on replacing the CCFL (or two in my case since its a dual lamp screen) and it doesn't look too difficult, however since I have a dual lamp screen it seems unlikely that this is my problem. How likely is it that they would both fail at the same time? My other thought is replacing the video cable since the connector that plugs into the inverter does seem like it may have some loose connections..I just don't want to continue wasting money on replacement parts that don't solve the problem

 

well if ur not going to spend anymore and need to buy a new one , get the ASUS G73... great specs for $1600... i'm getting that later on in the year... it shouldn't die as easily...

 

You never can rule out a GPU issue with these NVIDIA chips. Still, if an external monitor works it does seem unlikely.

Both lamps going out at the same time seems unlikely... so that leaves the internal monitor cable. Or the lid switch... try disconnecting that. The dv2000's had a terrible time with stuck lid switches. Not sure where it is on your model but it'll be a two pin cable, probably connecting somewhere near the top edge of the motherboard.