Dell 700m dark LCD repair 28 December 2006, 04:21
Posted by Orhan in : Geeky Techy Stuff , trackbackGet the Flash Player to see this player.
This is my first produced video. It is a technical “how-to video” on how to replace the LCD inverter module of a Dell Inspiron 700m laptop. After my screen backlight stopped working, I pinpointed the problem to the inverter module, which is not an easy to find item in USA. Therefore, I ordered it through Ebay from Hong Kong, ebay ID: pcsuperfreek, website: www.pcsuperfreak.com. Total cost: $60.00. The item arrived in record time, only 6 days. Putting it on took 7 minutes, because I learned how to do it during diagnostics.
I hope this information helps others out there having the same problem. Remember, if your laptop is still under warranty, use it. Do not attempt this repair procedure. Also, the procedure relies highly on your skills, meaning you can easily damage your laptop. Do it at your own risk. Good Luck 
Comments»
Thanks for making the video. I wish Ihad the patience to find it before attempted to repair same lcd. I was getting blue vertical transparent bands about an inch wide. Then a lot of multicoloured vertical lines on the right half of the lcd. When removing the lcd and checking connections (including the inverter) I lost the light. I susperct I have two problems now. To replace the lcd as well as the inverter.
What I realized after I put the new inverter was that the lid open-close sensor/switch at the upper left corner of the motherboard (which is activated by the little plastic pin on the hinge cover) was faulty. Maybe my inverter was OK at the beginning but I also shorted something on it while trying to check if it was ok. My backlight was actually going off because of the faulty switch. What I did is to eliminate its function and fix it to always on.
I am not saying that in your case it is the switch because you say you have irregular lines on your screen. I strongly believe it is your graphics adapter if not the LCD itself. Did you try with an external monitor?
Good luck..
I have the same problem. This has happened after spilling water on my laptop. I have the same problem, ie there is a faint image and I can connect to an external monitor.
What did you do to get the switch to be always on? I have the software settings set to do nothing when closed.
The switch under that little plastic pin had come apart. Luckily I did not lose the little slider in it which actually controls the on-off function. What I did was to understand how it worked, then fix it to its “on” position by the help of some hot glue. As far as I remember, as the switch is pushed down and released (comes back up under normal conditions) the slider in it slides on a horizontal basis. İt needs to be all the way towards the monitor side.
Since you say you spilled fluid on the laptop, my guess is that it might have gotten into the switch itself and affected its resistance. Do you ever get light back if you manually pushed the switch and released a couple of times maybe?
You might need to clean the contacts inside that switch and fix it to always on position. But you should keep in mind that the problem might also be something else, including the inverter module or the cable connections on the mb.
Good luck!
I have a similar 700m screen problem (a dark screen) which I have not identified the exact cause yet and I hope you can give me some clue. I think the video card is ok because I can use the laptop while connecting it to an external monitor. The pattern with the dark screen is that, say my machine is now in windows hibernation, when I open the lid and it is supposed to start to show the login screen. Sometimes I was able to see the login screen for a few seconds, then it went completely dark afterwards. Even when I reboot the machine, i won’t be able to see the bios screen. Do you think it is due to the faulty inverter? Thanks a lot. BTW, nice video!
It might not be the inverter. The symptom is very similar to what I had. I am almost certain that I broke my inverter myself thinking it was faulty and probing certain parts of it with a multimeter (I kind of shorted something while doing that!).
Anyway, I ended up ordering a new inverter, put it back on and it started fine but after a few minutes it went dark again. That is when I realized the problem was with the lid open/close sensor switch on the upper right side, above the keyboard. Try to gently push it and see if it affects anything. Remember, it might not affect at all even though it is broken. It might very well disintegrate during this test so leave it to Dell if your warranty is still valid.
If it disintegrates, you must not lose the main part of the switch that has the conducting surface on it. If this happens, you should fix it into place to have an “always-on” monitor. Otherwise you will need a new motherboard.
How did you arrive at the conclusion that the problem is with you inverter?
The problem was intermittant. This made me think that it was the inverter. But now I am almost sure that the real problem was the switch, not the inverter.
Orhan: I also have a 700m, same dim screen problem caused by a single drop of water down to where the inverter is. After watching your video, I was sure that the inverter was short and confident on DIY. So thank you very much! It was really very very helpful!
THANKS FOR POSTING THIS PAGE!!! After reading and watching your video, I decided to give it a shot. My screen was black all the time… when playing with the switch I would manage to make it blink for a second or less. Connecting to an external monitor worked just fine, so I guess it had to be just the display. Also, when it worked (during those few seconds) it would make a strange sound. So I ordered an inverter from Ebay (Dell Inspiron 700M 710m LCD Inverter Laptop T731011). I paid $50 plus $9 for shipping. Having watched the video, it probably took me 10 min to get it done… the only screw that gave me grief was the one hidden next to the lights…. I guess I didn’t watch that part in your video
After putting it back together, it WORKED just great! No weird sounds… just like before. Actually, this is my wife’s laptop… and she thinks that she spilled a few drops of coffee near the bottom of her screen… turns out that the part that I replaced had some coffee stains… she owes me big for putting back in shape 
Once again, THANKS for putting this video on the web!!!
Thanks for your post. Really Helpful. I have a similar problem myself. Bought a 700m two years ago when starting my masters. Now when I turn it on, it works fine (i.e. boots up, I can see the desktop) and then after a minute or two, just goes dim. The desktop is still there but I can’t see anything. However if I stick my head into the screen, I can see a faint image of the desktop. And when I shutdown the computer and restart it again, same problem in the same sequence. Do you think it is the inverter or some other problem? Would really appreciate your help.
I have a 700m that where the inverter is gets very hot when the laptop is plugged in, but is fine on battery power. It’s starting to mess up the screen a little bit. Do you think the inverter needs to be replaced?
I have a dell 700m.. My speaker wires broke recently and i took it apart. I turned it on to test everything got excited and put everything back with out turn it off… As i was screwing in the inverter board the screw driver accidenty touch the inverter board and my lcd went dark. If u look closely you can see the icons and background aim etc but the backlamp isn’t lighting up…
do i need to just replace the inverter board or the whole lcd?
jchow, yes it seems like you fried the inverter. Replacing only that will most probably be enough.
Majik, I really do not know if what you are experiencing is caused by a faulty inverter or not.
Orhan
i have a dell 700m that fell of my bed. The problem i am facing is that the screen stays pitch black every time i boot it up. when i tried to connect my dell to an external monitor, nothing shows up. im guessing that my video card or an inverter problem? please help! thanks
I am having the exact same problem as Irfan……”Now when I turn it on, it works fine (i.e. boots up, I can see the desktop) and then after a minute or two, just goes dim. The desktop is still there but I can’t see anything. However if I stick my head into the screen, I can see a faint image of the desktop. And when I shutdown the computer and restart it again, same problem in the same sequence.”
Is this the LCD inverter module?
Please help me if you can.
Hi There,
First, thanks for posting the video - made it possible to begin to troubleshoot my problem, which is:
Upon opening my Dell 700m the LCD screen lights up (works normal) and within 1-2 minutes max it shuts down. Sometimes it is barely visible but can’t even see the cursor/mouse. The external video works just fine. I didi replace the LCD inverter with one I know works and a new one, neither one did the trick.
The LCD comes on for a few seconds after opening and closing the laptop.
Anyone have any ideas on what to look for next?
thanks,
Erik
PS. I have fiddled with the plastic lid switch button and got nothing. I have not opened it up beyond accessing the LCD inverter.
My screen was black, but now it is gray. I will check all the leads, but I am not sure. I dropped the darn thing and the screen has acted this way ever since. Do you think I need to replace the enitre screen? I can see the image on my projector, but nothing on the lcd itself.
Thanks in advance
i’m thinking my laptop has the same switch problem. How did you solve it using hot glue? when i press on the little switch, the screen lights up for a second, and goes back to dim. I want to solve this as i have not been able to use my laptop without an external monitor for 6 months now!
Efneri,
There is a really tiny actuator just under the pin that goes up and down. In my case the pin itself got seperated from the switch body underneath. Anyway this little plastic thing is metal plated on the other side. This is what ensures conductivity when it is all the way up (towards the screen).
Very carefully, without losing the piece, you should slide it towards the screen as far as it will go. It also needs to be pushed against the motherboard firmly to maintain electrical contact. Then fix it to its location by the hot glue from the top. The switch will not be functional anymore but your screen will be lit all the time.
If you lose the piece, then you will probably need another motherboard. Be careful.
Good luck..
Hello fellow dell users, can anyone tell me if the 700m is supposed to get super dim when unplugeed and the battery becomes the power source? My guess is this is normal to add to battery life.
I saw nothing in the bios to keep the screen bright on battery power. Is there a way to make it stay bright?
Thanks
Orhan:
This message board rocks… you do a great job explaining technical matters in a meaningful way to others with les expertise.
I have a problem that is a hybrid of this discussion. Any insight is helpful!
1) I definitely have the issue where the my Dell D600 has the faint black screen. If you tilt the screen the right way, you can faintly make out that the OS is in fact running… so it’s not truly black…Windows is indeed running despite the black monitor. It’s likely the back lite being out, etc. If I plug in an external monitor, I can see the Windows screen running like it normally is.
2) The weird thing. If I turn on the computer using battery power ONLY — the laptop screen works *perfect*. The pseudo-black screen is *always* triggered by plugging in the battery adapter to the Dell. The minute I do this, the screen brightens for a very short period of time (maybe 1-2 seconds) — and then immediately settles into its black state. If I remove the power adaptor from the Dell, the screen stays black. In other words, once you plug in the adaptor, all bets are off — you are guaranteed ‘black screen until you shut down your computer, no matter what you do. The only way to get the screen back is to power back on — solely off of battery power. NOTE: The power adaptor DOES charge my battery just fine.
3) Also note — I have two power adapters (one of them nearly brand-new), and both cause the same problem once plugged into the Dell… so it’s not the adapter.
Based on all of the above documentation, what would you reccommend?
Any advice is truly appreciated.
With warmest regards,
Greg
I have the same problem, and I just wanted to know how to tell that it is definitely the inverter. Someone spilled a drink on my laptop, and the screen immediately went dark. The computer is fine now (other than the screen) and in fact, right after the drink was spilled and before i managed to unplug the computer, it was still playing music. I know it’s not the switch, because I set the computer to standby when the switch is pressed, which works, which means the switch is capable of turning off and on. Is the inverter the only other component that could be broken? Should I just take the plunge, replace it, and hope for the best, or is there a way I can check beforehand?
I didn’t see a response to this.. I am having the same problem as Ms. Reed. My fiance’s 700m was working famously until one of her students knocked it off her desk and now all I get is a gray screen. The backlight is working as far as I can tell and I get a crystal clear picture when I plug it into our LCD monitor. Any suggestions (other than my stupid comment of we’ll just buy another one which she didn’t seem to be as excited about as I) would be great! Thanks in advance
Steve, if you use the function (Fn) button along with the up and down arrows you will be able to adjust screen brightness with or without battery power and yes the 700m is designed to get super dim to save battery life
NO it shouldn’t get supersim, mine gets alittle bit dimmer, but not alot.
Thanks for this post, I was having this exact same issue and was ready to shell out for a new inverter or backlight until I read this about the switch. One addendum though: I found that I could take the switch apart and remove the slider, and this had the effect of being always on. If I understand the contact plates correctly, I think that the default is on, and only when the switch creates a short between the two plates does it switch to off. Seems a bit safer than gluing.
Anybody know what would cause a new inverter to go bad?
Hi, I’m suspecting the inverter of my Dell Inspiron 6000 has got some problem. LCD is down as backlight isn’t turned on. The inverter generates some kind of high pitch noise when the laptop is on. So good to have found this site. Many thanks to Orhan for sharing the knowledge. But I’m facing a problem - I’m not able to find the part to replace the original inverter (Sumida LTN154X-B2). Anyone here can offer some help?
Hi, I am having a problem with my 700M display after a liquid spill. The upper part of my screen (30%) displays like it should. The lower 70% consists of bands and the color is in different tones than what it should be. When plugged into an external monitor, it works just fine which rules out any problem with the display adapter. I ruled out an inverter problem by trying a brand new inverter but the results are the same. I am sure I don’t have the switch problem since the display stays on. Does anyone have any ideas as to what the problem might be?
hello, i dropped my laptop a dell inspiron 700m and the screen broke on one corner, i still could use it, i bought a new screen and installed it, but after i installed it, it did not work, you can see a grey screen only, no image, you can see the screen is on, but with no image, i plugged in an external monitor and it works, but the laptop screen doesn’t, does anyone know what could be the problem? thanks
I just want to add that this video was very helpful.
Also, I have a similar experience to add to the problems, although no immediate solution.
I spilled a good amount of water on the keyboard of my Inspiron 710m. I dried it out and miraculously resuscitated it. It worked just fine for about 4 months.
Then, I began having the nearly random backlight issues. Windows runs fine but the screen becomes barely visible. The only stopgap solution I’ve found is to keep the display ‘hot” - i.e. never allow it to turn off via power saver and keep it on and ‘warmed up’. This seems to work regardless of the power supply.
If I close the lid or allow the display to go out intentionally, I get the same problems when I resume until I close and open it enough times to ‘warm it up’ again.
Anyway, I purchased and installed a replacement inverter board. It booted up with a disply, then with 5 minutes made a nasty hissing noise and proceeded to act just like the old inverter board. New board, same problem.
Clearly there is a short related to the spill somewhere further up the display chain, but I am at a loss and considering just buying a monitor to use this as a desktop, or biting the bullet and buying a new laptop.
i have the same problem with the backlight above, image was faint and when plugged in an external monitor i can see everything. So follow up on what people been saying about the inverter. I bought inverter and screen come back up normal now. Thanks for all of you comments above to help me tracked down the right culprit.
The screen of my HP dv1000 is dim. In fact, it gets gradually dimmer from the right to the left side of the screen. The picture is clear, so I know it’s not the LED, it’s just dim. If I depress the hinge switch the LCD shuts off and is black, so I know that it’s not the hinge switch. Any suggestions what might be faulty? Anyone with the same gradiated dimness?
I also have the grey screen problem after having dropped my 700m that several other people have mentioned. It works fine on an external monitor, and the backlight for the LCD is clearly working, but it’s just a blank grey screen. I tried reseating all the cables to no effect. IT sounds like lots of us have the same problem. Any thoughts on what the solution might be?
johnny:
I think it could be the screen you bought is faulty, if you bought used, you never know if the person was honest about it or it was damaged on the handling. I would suggest you put the old one back see if works….the inverted can be damaged easily, so if the old one works it rules out inverter.
although trick, you can also remove the LCD CCFL BACKLIGHT LAMP I removed this light and tested by plugging it to the inverter…..this light is no the lower part of your screen covered by a foil, but you have to unscrew the whole screen to get it out….very time consuming and handle with care.
MOHIT I am having the same problem, but I do not know the cause….I ruled out inverter and the LCD CCFL BACKLIGHT LAMP, as I tested both but my case is the opposite the upper 70% is dark as if the inverter or LCD CCFL BACKLIGHT LAMP wasn’t working, but they are…..which leaves of no other theory, anyone has any idea what could be?????
Mouse pad: Another question about 700m.
Mouse pad not working, stopped working, at first it would work and the cursor would freeze in the lower part and get stuck.
I read a lot people having the same problem.
I ruled out mouse pad as I tried 2 different pads, none worked. It can’t be hardware as I reinstalled an updated etc…..
It could not be the OS or system problem as I swapped HD between two 700m with same and different OS and still didn’t work.
I read it can be motheboard problem????? but what kind of motherboard problem it could be???? is it fixable or soemthing not worth botheing with just use usb or wireless mouse?
Thank you
I see a lot comments about dimm lcd….once ii dropped my laptop and the plug that goes into the inverter came loose, but barely, so before you start buying inverters i would suggest checking the plug.
The inverter is your second option. Then comes the LCD back light this is a little tricky to get it out, it is a very thin light….
Inverter and the LCD light on ebay goes for $20 each with shipping.
It is worth trying to fix yourself.
A screen runs around $150 (used) but can go as high as $250 depending who is selling.
I guess since the 700m are getting older and more and more people are having problems we could swapp parts among ourselves….I have 2 mouse pads, a cover some other small spare parts.
I have a total of 7 dell 700m, from time to time I have to get parts out for upgrades…..
or some go bad I leave for spare parts.
Hi again,
Here is a picture of the problem I mentioned above:
http://www.zeroquest.com/ebay/2007-12-12/laptop2.jpg
Does anyone have any idea?
It is not inverter, not the back light, and not the cables, if I put the screen on another same model (700m) working computer with good iverter the same will happen…. I got the back light out and it is working ok without a problem.
I also put another screen from another computer, so it can’t be anything related to mother board.
Any ideas?
I dropped my 700m and the screen went blank. I hooked it up to my desktop monitor and the computer still works. I bought an inverter and that did not change anything. I bought what I was told was a brand new lcd from Japan. I installed that and that did not work. Do you think I should try the new inverter and new screen next? Or could it be another problem? Thanks for any help.
HELP, HELP, HELP.
Here is another 700m problem again. I had a black screen LCD, could see the desktop from some angle. I had read all your guys comments and watch the video very helpful infomation, thank you all. I had learn how to change the inverter, and check the sleep button, I did all that, but the problem still the same. My next step is try to change the back light, but don’t know where it locate at and how to change it…if anyone willing to give me some hint that would be very helpful…Thank you very much.
Orhan, thank you for sharing these computer repair secrets in your excellent video. Some drops of coffee fried my LCD inverter… I saw a few drops slip down into the crack between the screen and the frame just before it went black. I’ve never worked on a laptop, but with your help, I saved a lot of money and my screen works fine again. Thank you thank you and I wish you much good juju.
kim,
I did the samething today; spilled coffee on the screen and it immediately went down where the inverter was and the screen went black; though, if i look really closely, i can still see the icons (no backlight). Anyway, i am pretty sure its the inverter and ordered one which should be in a couple days.
I’ll post my result back after i install.
Orhan,
good post…
replaced the inverter;– and it works!
For others, if you spilled something on your laptop and liquid went on screen (and therefore went down to where inverter is)) it is most likely inverter — if you dropped your lap top i cant say as it could be a lot of things…
but for me…all i can say about this web post
i like it…
Hi! I want to thank you for putting up the video on how to replace the inverter. I bought the inverter on ebay and the project only cost 30.00 to do myself instead of putting out 180.00 for repair. If I only know it was going to be as simple as removing a few screws and pulling out 2 ends and popping a new one in I would’ve been surfing the net on this a long time back. I did take the panel apart after the screen went dark but there was one screw I couldn’t figure out how to remove (the one under the sticker that runs through the inverter) Your video showed me how to get it out. Thanks again!
Your post saved me! I found it the very day I spilled coffee on my laptop, got the piece from ebay, installed it with your help, and now it works like new! Thanks so much for sharing your expertise. Gotta love the world wide web.
I appreciate you posting the video so GOOGLE could find your page, but the most useful info was your post #6, “That is when I realized the problem was with the lid open/close sensor switch on the upper right side, above the keyboard. Try to gently push it and see if it affects anything.” I did this, and it turned out the sensor was stuck pushed in. Thanks for the post, saved me some time and headache figuring out if it was backlight or inverter.
I have a Dell Inspiron 6000 and I am almost certain it is my switch. The monitor stopped working the external works. I do get it to come on for about 2 seconds sometimes when I restart it.
My question, do you think it is the switch and where would the switch be located to test this out?
Thanks!
Thanks for posting your video. I have a Dell Inspiron 700m and im not sure if is the switch or if I should buy a new inverter. I have an horizontal line, at the begining it was only one thin line now is almost half an inch wide. Computer works perfect with an external monitor, no lines at all, that`s why I know it can`t be the motherhood.
Thank you!!!!!!!!!
Bummer. I have the no-backlight problem on my 700m. It works after booting for a minute or so, then shuts off. I replaced the inverter with no luck (the new inverter will go on ebay soon.)
If I get into the bios screen, I see that if I move the lid-closing switch, the backlight will go on and off (assuming it it within the first minute or two that it works), so this is not the problem. I am afraid this is video circuit problem even though it works great with an external monitor. Something is telling the backlight to go off…I just don’t know what that could be. I am open to suggestions.
Just in case anyone else runs into this issue….
I tried an experiment with a CCFL tube from an old display in place of the internal tube. The tube lit up as expected and did not shut off. So I guess the problem is just with the fluorescent tube. Since these only cost about $10, I am going to buy the proper size and gamble on it.
Final result on the backlight that would go out after a minute or so…see previous posts.
Replacing the CCFL tube solved this problem. DO NOT attempt to do this yourself! I have 30 years experience in microelectronics and I did not succeed in fixing this. This was VERY difficult. Yes, I replaced the tube and yes it solved the problem, but I also managed to crack the screen, which of course I cannot fix. So I now have a working display if you count having only 95% of the display visible as working.
Is there a tutorial available for replacing the backlight?
don’t know if my previous post went through. I’ll ask again.
Is there a tutorial available for changing the backlight in a 700M?
I have replaced LCD itself but still got the dark screen, the same problem I was having before..If I look very carefully I can see the icons and it works on an external monitor. Since new display gace me the same results, I replaced inverter board which didnt work..and then I replaced with the cables still the same problem.. I am thinking it can not be the CCFL tube since new display had the same issue. Since the chances of the new display having the same tube problem is very low, I am thinking it is the signal cable.
What do you think???
HI,
I did replaced the lcd inverter on dell 700m inspiron, work for
a minute, then back to square one, dark monitor scree.. what
is the next step in resolving the dark screen problem on Dell
Inspiron 700m lap top computer, thanks for your suggestions.
cliff
People read ALL the comments above. Orhan has explained several times that there is a notorious switch problem on the 700m that can cause the backlight to turn off after booting.
great post.. i got asked to pay $330 for a new lcd on my 710m today, after coming home and jabbing the switch a few times it now works perfectly again.. amazing.
i spilled water on my laptop and i purchased a lcd inverter and replaced it but it still doesnt come on. theres an one inch wide black vertical line. I dont know what else I can do other then replacing the whole lcd. thanks
Thanks! Just did this for one of my users at work. The video saved me a bunch of time!
After pouring the largest cup of coffee ever made entirely on my laptop I thought I was down $1000 for sure. This simple part switch was my last hope. Thank you so much because it worked like a charm!!! Orhan you rock!!!!