Let’s say the keyboard in your laptop stopped working properly and you decided to install a new keyboard yourself. You disassembled the laptop, removed the keyboard, tried to unlock the keyboard connector and… OHH! MAN!… a piece of the locking clip on the connector got broken!

What can you do? Unfortunately, you don’t have a lot of options. The keyboard connector is permanently soldered to the motherboard and cannot be replaced at home. If the connector was damaged, you’ll have to replace the whole motherboard, use the laptop with an external USB keyboard, or…. try the following trick. Hopefully it works or you.

The keyboard cable is locked inside the connector on the motherboard. In order to remove the keyboard, you have to unlock the connector and release the cable.

On the picture below you see one of the most common connectors. It has the base (white in my case) and locking clip (brown in my case). The keyboard cable is jammed between the locking clip and base.

To unlock the connector, you have to move the locking clip about 2 millimeters in the direction shown by two yellow arrows.

IMPORTANT! The locking clip must stay attached to the connector base.

After that you can pull the keyboard cable (green arrow) and remove the keyboard.

If you are not careful enough, you can move the locking clip too much and break it.

On the picture below you can see the locking clip is missing the left hook.

On the next picture both sides of the clip are broken.

IMPORTANT! Do not though away the broken clip even though it looks completely useless.

If you insert the cable into the connector and will not lock it with a clip, the cable will not make good contact with pins inside the connector and the keyboard will not work.

Here’s how to install the broken clip back in place and make it work.

Position the broken clip the way it was before. In my case both sides of the connector are broken. What could have been worse?

Carefully insert the keyboard cable into the connector. Note, in this type of connector, the cable goes above the locking clip.

Carefully push the broken clip back in place. You can use a small screwdriver to push on the clip behind the cable.

The clip fits tightly when there is a cable inside the connector.

Secure the connection with sticky tape and you should be good to go. The keyboard should work just fine.

The keyboard connector shown on the following picture is very similar to the previous one. The only difference – the keyboard cable is routed under the locking clip. Fix it the same way as the previous connector.

On the next picture you see another type of keyboard connector. The cable is inserted vertically.

In order to unlock the connector, you’ll have to move the locking clip (brown piece) about 2 millimeters up in the direction shown by two yellow arrows. After that you can pull the keyboard cable (green arrow) and remove the keyboard.

If you move the locking clip too far, you can break it.

In my example the right side of the clip is broken. But you still can use it!

Insert the keyboard cable into the connector, position the broken locking clip correctly (behind the cable in my case) and carefully push it in.

Even with a broken clip the cable will make good connection with the base and the keyboard should work.

Here’s the same connector shown from the opposite side. You cannot even tell if the locking clip is broken.

If this trick worked for you, it means I just saved you a few hundred bucks on the motherboard replacement.

1. Network port failure.

In most laptops the network port (aka RJ-45 port) is soldered directly to the motherboard. If for some reason the network port fails (I’m talking about hardware, not software failure), the whole motherboard has to be replaced.

Instead of replacing the motherboard, you can use a PCMCIA network card (aka LAN PC card). You plug this card into the available PC slot in your laptop and get a network port instead.

2. USB ports failure.

Most laptops have a few USB ports available and if one of them stops working, usually it’s not a big deal because you still have two or three working USB ports left. But what if all of them stopped working at once. Let’s say the USB controller on the motherboard went bad and the laptop stopped recognizing any USB device plugged in any USB port. Again, I’m talking about hardware, not software failure. In order to fix this problem you’ll have to replace the motherboard.

Alternatively, you can use a PCMCIA USB card. You plug this card into the PC slot and get two or four USB ports instead. It depends on the type of your PCMCIA card.

3. Internal wireless (Wi-Fi) card failure.

Most newer laptops come with an internal wireless card installed. In some models the wireless card could be easily access through the door on the bottom of the laptop. In other models, the wireless card is buried deep inside the case. What can you do if the internal wireless card fails? You can replace the internal wireless card with another one or use a PCMCIA wireless card instead.

4. Internal flash memory card reader failure.

Most newer laptops come with an internal memory card reader installed. You can plug most known flash memory cards into the slot and access the content right away. Usually the card reader is soldered directly to the motherboard and if it fails, you have to replace the whole motherboard or use it as is.

If you don’t want to replace the motherboard you can use an external USB flash memory card reader. All you have to do is plug the card reader into the available USB port in your laptop and it’s ready to go.

5. Internal CD/DVD drive failure.

You’ll find an internal CD/DVD optical drive in most laptops. If the optical drive fails and stops reading CDs and DVDs, it has to be replaced with a new one. Internal laptop optical drives are not cheap.

Instead of replacing the internal drive, you can use an external USB optical drive. Simply plug this drive into the USB port, let your laptop detect and install the drive and it’s ready for you. Also, you can use this optical drive with any other computer which is very convenient.

The screen inverter failure is very similar to the backlight lamp failure. In both cases the screen gets very dark and the image on the screen becomes very faint, barely visible under a bright light.

If you suspect the inverter board failure, I know only one reliable way to test that. It’s either replacing the inverter board with a known good one and see if it works, or connecting a known good backlight lamp and see if your presumably bad inverter lights it up.

In most cases I go with the second method – testing the laptop with a known good backlight lamp. Why? Because backlight lamps are pretty much universal. The same backlight lamp will work with many different inverters as long as they have matching connectors. I’ll talk about these connectors later.

The inverter board is located inside the display panel under the LCD screen. In most laptops you can access the inverter board if you remove the LCD screen bezel. The inverter board has connectors on both ends. The left side of the inverter is connected to the LCD cable. The right side of the inverter is connected to the backlight lamp which is mounted inside the LCD screen. Check out this display diagram.

To make sure that inverter board is getting power from the motherboard (via the LCD cable), you can test it with a multimeter. In my case I connected the “+” lead of the multimeter to the pin 1 on the connector and the “-” lead to the ground trace around the screw hole. I got about 19.4V DC on that side of the inverter, so it’s getting power from the motherboard.

WARNING! If you accidentally short something on the inverter while testing it, you can damage the inverter or even the motherboard. Proceed on your own risk! Not sure? Don’t do that!

So, the inverter is getting power from the motherboard, but the screen is still dark. Apparently, it’s either bad inverter or failed backlight. Let’s test it with a known good backlight.

Here’s what I’m going to do:
1. I will unplug the LCD screen from the right side of the inverter. Basically, I’m unplugging the LCD backligth lamp which is located inside the screen.
2. I will plug in my known good backlight lamp which you can see on the picture below. Please notice that my test backlight lamp is shorter than the screen, but for the test purpose that’s OK.

Results I’m expecting:
1. If my test backlight lights up, the backlight lamp inside the screen is bad and there is nothing wrong with the inverter board. If that’s the case, you’ll have to replace the LCD screen or replace the backligth lamp (which is not easy at all).
2. If my known good backlight lamp stays dark after I turn on the laptop, most likely we have a faulty inverter board. If that’s the case, you’ll have to replace the inverter board and it’s relatively easy.

There are two different types of backlight connectors, you can see them on the picture below. The top one (big) is not as common as the bottom one (small). I do most of my test with a backligth lamp which has a small connector.

IMPORTANT! If you decide to buy a new backlight lamp for test, you have to make sure that the connector on the lamp matches the connector on the inverter. Very often backligth lamps are sold without any wires attached. If you plan to use this backlight as a test equipment, you’ll have to find one with wires as I have on the picture 3.

You can buy a cheap backlight lamp with wires here.

Finally, when you ready to test the laptop, unplug the LCD screen from the right side of the inverter.

Plug in your test backlight lamp and turn on the laptop.

In my case, the backlight lamp lights up, so the inverter board works properly.

Check out my previous post about troubleshooting laptops with backlight failure.

The internal copper sleeve has been removed and cannot be installed back. If you solder the power jack back on the motherboard without this sleeve it might work but the connection between the “+” lead and motherboard will not be reliable.

In the following guide I explain how to fortify a damaged power jack connection. You can use this repair technique in some laptops with similar power jacks.

You can remove the copper sleeve from the power jack with a soldering guy and through it away. You cannot install this sleeve back into the terminal on the motherboard.

Find a small resistor or capacitor with thin leads. Cut off one of the leads. I’m going to use it to fortify the connection between the power jack and motherboard.

Shape the lead as it shown on the picture below.

Put the lead on the “+” connector on the power jack.

Solder the lead to the power jack.

Now I’m going to modify the “+” terminal on the PCB. Even though on the picture below it looks normal, it’s damaged inside (the internal coating has been removed).

Carefully scrape off green varnish around the whole on the “+” terminal on the PCB. You can use a small flathead screwdriver.

If the whole is not big enough for your modified power jack, you can widen it with an awl.

As you see on the picture below the whole on the terminal has been widened. Apply a fresh coat of solder on the clear area of the trace.

Install the power jack assembly on the motherboard. Make sure there is no gap between the jack and motherboard.

Here’s a view from the top side of the PCB.

Solder all pins except the modified “+” pin.

Now, when the power jack is secured, you can shape the lead as it shown on the picture below.

Solder the lead to the terminal. Remove excessive flux with an old tooth brash soaked in 99% alcohol.

Here’s a view from the bottom side of the motherboard.

Be very careful. Doing this modification you can damage the motherboard and make it unusable. Proceed on your own risk.

My first option was using the external USB Bluetooth adapter as is but it wasn’t very convenient. I decided to find a way to install this adapter inside the laptop.

Before I started hacking my laptop, I installed Bluetooth software and tested if the new adapter works fine. As you see on the picture below, the Bluetooth icon in the SysTray is active and the cell phone is detected.

For this modification you’ll need:
1. Laptop disassembly experience. Here are service manuals for some laptops.
2. Soldering skills and tools as I mentioned in the power jack repair post.
3. Inexpensive USB Bluetooth 2.0 adapter. I spent less than $8 for that thing and you can find it even cheaper.

This is only for experienced technicians. If you have no experience you can (and most likely will) damage your laptop. Proceed on your own risk!

This guide should works for all laptop brands: Toshiba, Dell, HP/Compaq, IBM, Lenovo, Gateway, etc… as long as you have enough space to mount the Bluetooth module inside the laptop.

OK, here’s how I did it.

First of all, I disassembled my laptop and found a place where I can install the Bluetooth adapter. In my guide I’m using a Toshiba Satellite A105 laptop. I found enough empty space in the top right corner of the laptop.

My idea was simple. Disassemble the Bluetooth adapter, remove the Bluetooth module and solder it to one of the USB ports. I decided to use one of the USB ports located in the lower right corner.

NOTE: After this modification is done, you will not be able to use that particular USB port with any other USB device, it will not work because it’s dedicated to the Bluetooth module. But I think it’s not a big deal because most laptops have 3-4 USB ports.

I found some thin wires laying around.
Make sure that wires are long enough for your project.

Now you’ll have to disassemble the adapter. I easily split the adapter case with a sharp knife and removed the Bluetooth module.

Unsolder the USB connector.

As you see on the picture below, the Bluetooth module easily fits into the empty place inside the laptop.

I soldered four wires to the Bluetooth module. I used terminals for the USB connector.

After that I soldered four wires to four contacts on the back of the USB connector. Be careful. Make sure all wires are connected correctly.

At the last step I installed the Bluetooth module into the place and routed wires from the module to the USB port. I had to reroute the wires a few times to make sure that I can install the top cover and it seats properly. I secured wires to the motherboard with electrical tape.

Finally, assembled the laptop and tested it. There is no on/off hardware switch for the Bluetooth module but I can turn it on and off through software.

The Bluetooth adapter has been installed INSIDE the laptop and works flawlessly!

First of all, I assume that your new LCD screen is compatible with the old one. Different screens require different video cables. Make sure you new screen is compatible with your laptop.

OK, let’s say you accidentally damaged the LCD screen in your laptop. A part of the screen still works fine but you cannot use it like that so you decided to replace the screen yourself. You can find LCD replacement instructions in service manuals or this DIY site.

You did some research and purchased a compatible screen, installed it into the laptop, turned it on and… The new screen is not working!!! What could be wrong?

Before you start to panic, check all cable connections again. Check connection between the video cable, LCD screen and inverter board. Reconnect cables just in case.

Take a closer look at the connection between the video cable and LCD screen. It’s possible you accidentally pulled the video cable from the connector during the screen installation.

The video cable has to be seated properly, all the way down.

Also, on some older LCD screens there are very thin pins inside the connector. Take a look inside the connector, make sure there are no damaged (bent) pins.
You can straighten bent pins with a very small screwdriver but this procedure requires a lot of patience and concentration.

Fortunately, most newer LCDs have a different type of connector, without fragile pins inside.

OK, you have reseated all connectors and cannot see anything wrong but the new screen still is not working. What’s next?

Remove the new screen and connect the old one. If the old one works properly (except the damaged area) but the new one is dead, apparently the new screen is defective and has to be replaced. Hopefully it has warranty.

Here’s another scenario. The new screen kinda works. You can see a very faint image but there is no backlight.

If that’s the case, disconnect the new screen from the inverter board and plug in the old screen instead, as it shown on the picture below. If the backlight inside the old screen lights up, apparently the new screen has defective backlight lamp and has to be replaced.

Related post: Laptop has bad video on the LCD screen. What is wrong?

I removed the battery and tested the laptop again. The laptop starts fine from the DC adapter when the battery is removed, but as soon as I start moving the power cord the laptop shuts off. It looks like the laptop looses power immediately.

If you have a problem like that, most likely it’s related either to the power adapter or the DC-IN power jack.

First of all, I tested the power adapter with a multimeter. The power didn’t cut off no matter how badly I moved the cord. The power adapter output voltage was 15.45VDC all the time. That means there is nothing wrong with the power adapter and most likely there is a problem with with the power socket inside the laptop.

By the way, I just purchased a brand new FLUKE 179 multimeter here for less then $160. The retail price at Sears for the same multimeter is $240. FLUKE is a really good brand. Just a side note.

Now I’m going to test the power socket inside the laptop.

In order to access the power socket I had to disassemble the laptop and remove the top cover assembly with the display.

You can find disassembly instructions for many HP, Dell, IBM, Lenovo, Sony and Toshiba laptops in these service manuals and guides.

In the laptop I was fixing (Tecra M2) the power jack is attached to a DC-IN harness and this harness can be unplugged from the motherboard.

As you see, I removed the DC-IN harness from the motherboard, plugged in the power adapter and tested continuity with my multimeter as it shown on the picture.

When the power cord is still, the voltage output is 15.45VDC, the same as on the plug.

But as soon as I start wiggling the plug inside the jack, the power cuts off and voltage goes to 0. It means, the power harness is bad.

The problem was fixed after I replaced the defective DC-IN harness with a new one.

In some laptops the power socket (DC jack) is soldered to the motherboard.
If the battery stops charging when you wiggle the power plug inside the jack, either you have a bad power adapter (test it with a voltmeter) or the power jack is broken or loose.

You cannot simply unplug the jack and replace it with another one. You’ll have to unsolder the old jack and solder a new one back on the motherboard as I described in this post.

If the power jack is not broken but loose (not making good contact with the motherboard) you can resolder the old jack without replacing it with a new one.

Let’s take a look at two different scenarios.

Example 1. The laptop is absolutely dead.
When you plug in the power adapter and press on the power button, there is no signs of life at all. The laptop will not make usual noises, LEDs will not light up, the fan will not spin, the screen is blank and black, etc… In short, the laptop is dead.

What you can do in this case?
1. Make sure the wall outlet is working and the laptop DC adapter is getting power from the outlet. Try another wall outlet.
2. Test the laptop DC power adapter, make sure the voltage output is correct. You can test the DC power adapter with a voltmeter.
3. Let’s say the DC adapter is fine and the adapter outputs correct voltage. In this case unplug the power adapter from the laptop, remove the battery, wait for 1-2 minutes, plug in the adapter and try turning on the laptop again.

OK, you tested the adapter and it’s bad. If you decide to replace the original DC adapter with a generic one, you’ll have to follow this rule:
The voltage output on your new adapter has to be exactly the same as on the original adapter. The amperage on the new adapter could be the same or higher.

If nothing helps and the laptop is still dead, apparently the motherboard is fried or there is a problem with the DC power jack. It’s possible the DC power jack is broken and the motherboard is not getting any power from the adapter. In this case you’ll have to disassemble the laptop and replace the power jack. Check out this guide for fixing laptop power jack.

Example 2. When you plug the DC power adapter and press on the power button, the laptop starts making normal noises, the LEDs work properly but noting appears on the screen. The laptop will not start.

First of all, take a closer look at the LCD screen. Look at the screen under bright light. It’s possible that the image is still on the screen but it’s very faint. If that’s the case, check out these tips for troubleshooting laptop with backlight failure.

If there is no image on the laptop LCD screen, test the laptop with an external monitor. Connect an external monitor to the VGA port on your laptop and turn the laptop on. You can toggle video output between the internal LCD screen and external monitor by pressing Fn and F4 keys simultaneously on HP laptops, Fn and F5 keys on Toshiba laptops, Fn and F7 keys on IBM laptops. Other laptops may use different key combinations.

Let’s say the external monitor works fine but the internal LCD screen has no image at all. If that’s the case, your problem could be related to the LCD screen or the video cable. Also, make sure the video cable makes good connection with the motherboard and the LCD screen. Try reconnecting, reseating the cable.

In my case, both internal and external monitors were absolutely dead. Neither of them had image. That means the problem is not related to the LCD screen or the video cable. From my experience I know that this problem could be related to the laptop memory.

Try reseating the memory module, maybe it’s not making good connection with the memory slot. Try cleaning contacts on the memory module with pen eraser. Try moving the memory module into another slot. Try replacing the memory module with another known good module, it’s possible that your original module is dead.
If you have two memory modules installed you can try removing them one by one, it’s possible that one of the modules is bad. Try installing different memory modules into different memory slots.

In my case reseating, swapping the memory module didn’t help. I was pretty confident that my problem is not memory related and I moved on.

Try removing battery, hard drive and DVD drive and turning on the laptop without these components.

Also, try turning on the laptop with an external monitor when the video cable is unplugged from the motherboard. If the laptop start with video on the external monitor, apparently there is something wrong with the laptop display panel.

In my case removing the hard drive and DVD drive didn’t help. Unplugging the video cable didn’t help either.
I continued taking my laptop apart piece by piece and tested it after each step.
I removed wireless card, modem, disconnected the keyboard but it didn’t help.

I still wasn’t able to boot the laptop with video on the external monitor.

Finally, I disassembled the laptop and removed the motherboard.

On this picture you see my final test. The motherboard has been removed from the base and I assembled basic barebone system on my bench.
1. Motherboard. Like on most laptops, in my case the video card is integrated into the motherboard
2. CPU with heatsink and cooling fan.
3. Known good memory module.
4. The power button board witch I need to turn on the system.
5. Working DC power adapter.

Still cannot get any video on the external monitor. The system turns on, the cooling fan starts spinning but there is no video.

At this point I’m 95% sure that the motherboard is dead. CPU failures are not very common, so it must be bad motherboard.

Here’s an example of a laptop with white screen. When you turn on the laptop, it starts but the image on the screen is completely white right from the beginning. In my case it was a Toshiba Satellite M45 laptop but this problem may occur with any other brand.

Most likely you still can use the laptop with an external monitor. Just connect the monitor to the VGA port on the back or side of your laptop and then switch the video output from internal to external mode.
On Toshiba laptops you can toggle between internal and external screens using Fn+F5 keys. Hold down Fn and press on F5 until you get video on the external monitor.
On IBM laptops use Fn+F7.
On HP laptops use Fn+F4.
It’s possible that you have to use a different key combination on your laptop but you get the idea.
On some laptops, in order to be able to use the external monitor, you have to connect it to the laptop and then restart the laptop so the external monitor is detected by the laptop.

I noticed that in some cases the laptop screen may turn white because of poor connection between the video cable and the LCD screen. If you want to check this connection, you’ll have to take apart the display panel because the connector is located on the back side of the LCD screen.
These laptop service manuals and disassembly instructions may be useful.

I always check the video cable connection first. Reconnecting the video cable may fix your problem.
If reconnecting the video cable doesn’t help, most likely you have a problem either with the LCD screen or with the motherboard.

The best way to find out witch one is causing the problem is testing the laptop with another working LCD screen. Without this test you’ll have to guess because as I mentioned before this could either bad motherboard or bad LCD screen.
You’ll have to disconnect the video cable from the LCD screen (connector 2) and the inverter board (connectors 3 and 1). After that you connect another working screen and test video.

For this purpose I’m using one of my test LCD screens. My test screen is cracked and because of that you see a wide white band in the center but it still works fine for this test.
The original screen is white but my test screen works normal (except the crack of course) and I can see the image. After this test I can tell that the problem must be related to the screen.

After I assembled everything back together and connected the original LCD, it’s still white.

CONCLUSION. In my case this problem is related to the LCD screen and it has to be replaced.

I’ll take as an example my Dell Latitude C840 laptop. As you see on the picture, it has a slot for the wireless card and one antenna cable. That’s strange, most laptops have two antenna cables, white and black. One cable goes to the main connector on the wireless card, another cable goes to the auxiliary connector. Probably you’ll ask me which antenna cable connects to which connector? I think it doesn’t really matter because both antenna cable are identical.

My main concern was finding the right device driver for the wireless card I plan to install into my laptop. As you know, without correct driver it will not be recognized by the operating system and will not work at all.
Likely, I have a spare wireless card from another not working Toshiba laptop and this card worked perfectly.
You can find this wireless card by the model number: WM3B2200BG. Just search by the model number here and you’ll find one for about $20. It’s a 802.11 b/g wireless card, so you’ll get a 54Mbp/s connection as I did.

In order to install the wireless card into the slot, just push it into the slot at a 30 degree angle (step 1) and then press on the card (step 2) until it’s locked.

After the card is locked in the slot you can connect the antenna cable. In my case, I snapped the antenna cable on the main connector. If you have two antenna cables, snap one of them on the main connector on the wireless card and another one on the auxiliary connector. As I mentioned before, I don’t think it matters with cable goes to which connector. Both antenna cables are identical.

Finally, you’ll have to download and install the wireless card driver. If you use the same card as I did (WM3B2200BG), you can download driver from the Intel website here.
Use this link: Intel® PRO/Wireless 2200BG Network Connection. Select the operating system, download and install the driver.
You have a couple of different options:
1. Download and install the driver only. Use this option if you want to use Windows wireless connection utility. That’s what I did because I prefer using Windows tools.
2. Download and install both the wireless card drive and the connection software. Use this option if you want to use Intel’s software application. It’s totally up to you.

As you see on the picture above, the wireless card successfully connected to the wireless access point at 54Mbp/s.