Example 1.

Laptop detects the battery but shuts off when AC adapter unplugged.

When you move the cursor arrow over the battery icon while the laptop is connected to AC adapter, it show the remaining battery charge and says “charging”.

The batter power meter utility (if available) also shows that battery is connected and charging.

But… as soon as you unplug the AC adapter, the laptop shuts off completely.

Possible problems:
1. The battery not seated correctly. Try reconnecting the battery.
2. The battery contacts got dirty or oxidized and the battery is not making good connection with the motherboard. Try reconnecting the battery a few times.
3. If reconnecting the battery doesn’t help, most likely the battery is bad and has to be replaced.
4. If you replaced the battery but the problem still exists, this is motherboard related failure. Apparently the battery charging circuit has failed. In this case the whole motherboard has to be replaced (or repaired on component level).

Example 2.

The battery not detected by the laptop.

The battery is installed and you know it’s connected correctly but there is a red cross on the battery icon.

If you move the cursor arrow over the battery icon, it says “no battery detected”.

Possible problems:
1. Most likely the battery is bad. You have a very good chance to fix this problem by replacing the battery.
2. If replacing the battery doesn’t help, this is motherboard related failure. The motherboard has to be replaced (or repaired on component level).

Example 3.

The battery discharges very quickly after it reaches some critical point.

The battery detected by the laptop and charges properly to 100%.
When you unplug the AC adapter, it take normal time to discharge until some critical point (let’s say 80%) but after that the battery discharges very quickly to 0%.

Possible problems:
This is battery related failure. The battery is bad and has to be replaced.

Example 4.

The battery charges only if the power plug positioned correctly.

You have to wiggle the power plug in order to charge the battery. After you find the right position, the battery charges properly.

Possible problems:
1. AC adapter failure. The AC adapter power cable is damaged. You can test your AC adapter with a voltmeter.
2. If the AC adapter works fine, most likely this is power jack (connector where you plug power adapter) failure. In this case the power jack has to be replaced.

In some laptop models the power jack is not soldered to the motherboard, it’s attached to a power harness.

In this case, you can unplug the failed power jack from the motherboard and replace it with a new one.

Also, this fix might work for the following HP/Compaq laptop motherboards: HP Pavilion dv2000/dv6000/dv9000, Compaq Presario V3000 and probably some other models. If it works for you, please mention the model number in the comments after the post.

Proceed at your own risk only if you have nothing to lose. Otherwise, close this page and take your laptop to the professional repair shop.

Problem description: I had an abandoned Compaq Presario V6000 laptop. The laptop was turning on when I press on the power button but after a few seconds turning off by itself. There was no video on the laptop screen or external monitor. I tried another AC adapter, new memory modules but it didn’t help. I was pretty sure this is motherboard related failure.

Research: After I did some research on the Internet, I found that this is a known problem with Pavilion dv2000/dv6000/dv9000 and Presario V3000/V6000 motherboards and most likely related to the graphics chip failure. The graphics chip (aka GPU or video chip) is soldered to the motherboard. Apparently, there are bad solder joints between the graphics chip and motherboard. Overtime the graphics chip separates from the motherboard causing all kind of different video problems.

Possible solution: One guy suggested baking the failed motherboard in a conventional oven preheated to 385 degrees Fahrenheit for exactly 8 minutes. This process should reflow the graphics chip solder joints and give the motherboard a second life.

I had nothing to lose and decided to give it a try. Here’s how I did it step by step.

First of all, you’ll have to disassemble the laptop and remove the motherboard.

STEP 1.

Remove all peripheral components installed on the motherboard (memory, cooling module, CPU, etc…). Remove all protective films from the motherboard. The motherboard will be baking at a very high temperature and all that can burn has to be removed.

Tip: Make lots of pictures while stripping down the motherboard. They will help you to put all removed protective films back in proper locations.

STEP 2.

Here’s how the same side of the motherboard looks without protective plastic films.

You can see the problematic graphics chip, it’s on the right side from the CPU socket.

STEP 3.

Remove all protective plastic films from the other side of the motherboard. Disconnect the audio cable.

STEP 4.

The motherboard will be seating in the oven on the baking pan. In order to elevate the motherboard above the baking pan I’ll use a few screws.

STEP 5.

I installed screws in four corners of the motherboard. There are plenty holes for screws.

STEP 6.

You can see there is a 3/4 inch gap between the motherboard and desk surface. By the way, I positioned the motherboard so the graphics chip seats on the top.

STEP 7.

Place the motherboard on the baking pan. Make sure it’s not touching anything.

Preheat the conventional gas oven to 385 degrees Fahrenheit and place the motherboard in the middle of the oven for 8 minutes. You’ll smell some burning plastic in about 6 minutes.

After that remove the baking pan with motherboard and let it cool down for about 30-40 minutes.

Install the motherboard back into the laptop, assemble the laptop back together and see if it works.

This fix worked for me! After I assembled the laptop, it started properly right away taking me to the BIOS setup menu. I didn’t have the hard drive, so I tested my laptop with a Knoppix live Linux CD. The laptop video works great!

I’ve been getting these questions many times and today I show how to disassemble a laptop keyboard. You decide if it’s possible and easy or not.

By the way, in one of the previous posts I explain how to fix individual keys on a laptop keyboard.

I’m doing it for fun. I’m working on a damaged keyboard and have no intention to use it in the future.

First of all, you’ll have to remove the laptop keyboard.

For the keyboard disassembly I’ll be using one of my tools shown on the following picture.

STEP 1.

Remove sticky tape securing the keyboard cable to back of the keyboard.

STEP 2.

Part of the keyboard cable is glued to the keyboard. Carefully separate the cable from the keyboard.

STEP 3.

Start peeling off the aluminum protective film

STEP 4.

Remove the protective film.

After the protective film is removed it’s really hard to attach it back to the keyboard because it’s deformed.

STEP 5.

Most laptop keyboards have some kind of plastic separators.

These separators secured on the back of the keyboard.

Plastic pins are melted on the back of the keyboard and retain separators in place.

Push all plastic pins though wholes on the keyboard.

Start removing the separator.

The plastic separator has been removed.

STEP 6.

Now you’ll have to remove all key caps.

Before you start removing key caps, make a picture or xerocopy of the keyboard so you know the order in which keys are attached to the keyboard.

In order to remove the key cap carefully lift it up with your fingers.

Remove the key cap so the hinge underneath stays connected to the keyboard.

Some big keys have a different design.

In addition to the hinge, some big keys (Back space or Space bar for example) might have an additional support bracket.

Remove the key cap with the support bracket. As you see, the key hinge stays connected to the keyboard.

STEP 7.

Some laptop keyboards might have blank covers on the left and right sides from the up arrow key.

Lift up and remove the blank cover.

All keyboard key caps and plastic separators have been removed.

STEP 8.

Now you can start removing key hinges – key lifting mechanisms.

Carefully separate the key hinge from the keyboard.

Each key hinge has two parts – external and internal pieces.

When you remove the hinge, try to keep these parts connected to each other the same way they are connected on the keyboard.

If the external and internal pieces got separated, you can assemble them together.

On the following picture you see the lifting mechanism (hinge) assembled.

As I mentioned at the beginning, I’m taking this keyboard apart just for fun. That’s why I don’t care about removed parts.

If you following this guide to repair the keyboard, I would recommend to keep all hinges in the right order.

STEP 9.

The keyboard has two sheets laying one on the top of another.

Remove the sheet with silicone (or rubber) nipples.

STEP 10.

Remove the second sheet with traces.

Both sheets have been separated from the keyboard base.

STEP 11.

The sheet with traces has two layers and all traces are running between these layers.

STEP 12.

In order to access and repair traces you’ll have to separate to layers from each other.

The keyboard has been disassemble.

As you see it’s not easy to disassemble a laptop keyboard and even harder to put it back together.

Is it worth repairing? Probably not. These days you can find a brand new laptop keyboard very cheap.

If you successefuly fixed your keyboard, please share your experience! Let us know what was wrong and how you repaired the problem.

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 brush 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.