Colorado Fisherman Forum banner

1 - 6 of 6 Posts

·
Registered
Joined
·
935 Posts
Discussion Starter #1
The backlight on my laptop's LCD screen is crapping out. It blinks in and out, and occassionally, my screen goes black. Anyone out there replaced the backlight diode on a laptop LCD before?

This sucks. :mad:
 

·
Registered
Joined
·
935 Posts
Discussion Starter #3
It's holding up for the moment, but I'll probably have to drop a few bills I don't have to get a new display for the d%$# thing.
 

·
Registered
Joined
·
6,797 Posts
i just had to replace the lcd on my laptop, fortunatly it was under an extended warranty

what model laptop is yours?
 

·
Registered
Joined
·
163 Posts
Most laptops over a couple of years old have a "Cold Cathode Flourecent Tube" (CCF) as the backlight. Some newer laptops use Light Emitting Diodes (LED) backlights. LED backlights are hard to manufacture in large sizes, but offer superior life and reliability. If I had to guess, I'd say that more than 75% of current generation laptops still use CCF.

Ok, that being said, you still want to know how to fix one... In short: Unless you're unusually small (smaller than an omp-a-lom-pa), have a PhD in oragami, or have a certain addiction to pain I would recommend that you don't try to fix it yourself. Either that or you've reached the point where you're going to throw the thing away and have nothing to loose for trying. I speak from experience here, after fixing literally hundreds of computers and at least a handful of laptops.

The main problem is that the backlight on laptops is not made to be serviced. It took an army of little people (kids in sweatshops, I'm told) to jam all those electronics into something a fraction of an inch thick and there's no way in hell you're going to get it out. Think about the stereotypical kids closet that is jam packed with toys, floor to ceiling, and just waiting to burst open. That's the LCD screen. If you did manage to open it up, the odds of you closing it up again is slim to none. Hence the requirement of a PhD in oragami.

Ok, that being said... Backlights on LCD's tend not to fail. CCF and LED's tend to dim over time. When they do fail, CCF's will fail to light up at all. LED's will fail one by one (there are many small LED's for one screen). They don't tend to fail by blinking on and off.

What does fail in laptops, and is the cause of most failures in laptops, is the wires that connect the screen to the base. These wires pass through the hinge and are constantly flexed. This flexing causes the wires (or the solder joints, or the connectors) to fail. You see similar things in cell phones and camcorders with a swiveling view screen.

If a wire breaks, but the insulation doesn't, then you'll have an intermittant connection and your backlight cuts in and out.

So... If you do decide to fix it yourself then focus on the hinge and the wires going through it. Odds are better than 90% that you'll find the problem there. Even so, better brush up on your oragami...
 

·
Registered
Joined
·
935 Posts
Discussion Starter #6
Well, I am good with electronics, but I have determined now that I don't want to take the LCD apart and try to replace it's backlight. What was happening is that the screen had been slightly red at startup for a few weeks (a common problem I have read about called "red screen" duh!!), and then began to flicker one day, followed by the backlight would going out after awhile. I can still see the display if I look closely, but it is way too dark to use. It happens within seconds of turning the screen on now. I have took the screen and some of the case apart a couple days ago to test the wires and connections, which are all good. After all the troubleshooting, it looks like the backlight has a problem, and the integrator is shutting it down. If a new display doesn't solve the problem, I'll be replacing the integrator.

The laptop is about 3 years old, but it's really my workhorse. It is a desktop replament. The extended warranty ran out only recently, so I have to pay for a new display, myself.

Sony Vaio (GRX line) with a 16.1" screen. I priced new LCD's and they are running $500 - $900, but given the age, I will probably get a new laptop in about a year. So, I just ordered a working used LCD for it for $200. If it doesn't last very long, I can afford to get another for the same price more than I can afford to pay $500 + for a new one, at this point.

Anyway, thanks for the info and advice. It help me know what to look at and make a decision on what to do about the problem. For now, I have other monitors in all the places I work that I have been able to attach, and they work perfectly (confirming that the video chip and circuitry are still good.
 
1 - 6 of 6 Posts
Top