Disclaimer This information is provided as an "At Your Own Risk" procedure. I can not absolutely assure that it is safe for any or all equipment, with any make of materials, or under any or all environmental or working conditions. If you perform this procedure on a product belonging to you or another person, you do so at your own risk and liability.
¾ Thieves steal according to opportunity, and even if they are aware that a laptop might be protected by a password, they will likely steal it anyway. If they can't break the password, they can just throw it away, as it did not cost them anything, and has no investment value to them.
Introduction An explanation of what's going on with the laptop. This is the prepatory section where I explain some things about the chip, CMOS, asset and service tags, and passwords; so that you will have a good grasp of the big picture. Hopefully it will also clear up any thing you have gotten a vague idea about on another website. All computers have special chips inside them that store information about the computer.
If a certain laptop does not correspond to any of these diagrams, more information might be found on the web, or, anyone not reading for informational purposes only - could decide to simply "Wing it." Also, the chip containing the password may be in a different location on some motherboards, but it should be able to be found by reading the numbers on the top of the chip, although a magnifying glass might be necessary.
Latitude c610 Yes Yes Picture included. Latitude c640 Yes Yes The Chip is on the bottom of the motherboard just to the left of DIMM 1. Latitude c800 Yes not tested no Info Yes Yes Picture included. c810 Latitude c840 Latitude L400 Yes Yes remove CMOS Battery for 5 minutes. Latitude D400 Yes Yes Picture included. Latitude D410 Yes Yes Picture included. Latitude D500 Yes Yes Picture included. 24c04 Yes Picture included.
Inspiron 2650 ? not tested no Info Inspiron 510m Yes Yes 24c04 eeprom is under a piece of black sheet under the pcmcia socket Inspiron 3200 Yes No A program called KILLCMOS.EXE is reproted to work for this laptop. Inspiron 3500 24c164 Yes Picture included. Inspiron 3800 Yes Yes The Chip is on the top side of motherboard, under MMC2 processor module. Inspiron 4000 Yes Yes The Chip is on the bottom side of motherboard, under the PCMCIA card slots.
Inspiron 1100 Yes Yes Chip is on the bottom of the board. 24c168 is near the B ram connector Yes Yes Picture included. 24C04 Yes The chip (C24O4N) is located on the bottem of the laptop right next to the two DIMM slots 1200 Inspiron 2200 XPS Gen2 Inspiron M170 9300 Now we are informed and ready to begin. Anyone attempting this procedure should have the implements shown in this picture, along with any others they may deem needful or useful.
* NOTE: There are a few things that should be addressed before you continue... I will list them quickly here. Some of these laptops may have an additional password called a "Hard Drive Password." This may not even become evident until the other passwords have been cleared. This password is stored on the hard drive, it does not mean that the laptop can not be used; it just means that the hard drive can not be accessed.
(Remember that SIMM / DIMM memory modules / sticks are always extremely susceptible to ESD damage at any humidity, under any environmental conditions, and should always be handled with the utmost care and precaution against damage.) The first thing that needs to be done, is the removable of any batteries, floppy drives, CD-ROMs, PCMCIA cards, or other removable / swappable components of the laptop. Also the power cord / adapter should be disconnected.
The hard drive caddy is pulled and slid outwards until it is free from the laptop assembly. The next thing that needs to be done is the removing of the keyboard. (This particular model) The keyboard is released from the rest of the assembly by the removal of 7 screws on the bottom of the laptop. These are indicated here by blue arrows: They are also indicated on the bottom of the laptop by a circle with the letter 'K' inside of it next to the location of each screw.
The keyboard is then lifted upwards and out of the main laptop assembly, except for 2 thin connection cables. The keyboard can then be lain perpendicular to its original position so that these cable's connectors can be accessed. The larger cable pictured here can be pulled straight up, disconnecting it from the main board. The retention clip of the smaller cable must be pressed on both sides (in the direction of the cable) gently.
The cable can then be pulled from the connector.
Step Two Taking it apart, continued. The rest of the disassembly process. The next thing that needs to be done is removing of the palmrest. (This particular model) The palmrest is released from the rest of the assembly by the removal of 5 screws on the bottom of the laptop. These are indicated here by red arrows: They are also indicated on the bottom of the laptop by a circle with the letter 'P' inside of it next to the location of each screw.
Now the latch pictured here must be released from its hold on the bottom of the case. I used a small flat screwdriver to gently pry it back while easing the front of the palmrest upwards. Be careful not to lift the palmrest up too much, as there are still 2 more hitches securing it to the rest of the case. There are 2 latches, one on each side of the palmrest. They are towards the back of the palmrest, near the screen.
The official repair manual for this laptop stated that the display must be removed before the palmrest can be taken off. But, as you can see, for anyone who is mechanically inclined enough to be able to cross a country road, this is not actually necessary. (Although this procedure does require the removal of the screen, which is next.) The first thing that needs to be done when removing the screen is to disconnect this ribbon cable from its connector on the motherboard by pulling it upwards.
After these screws are removed, the screen can be lifted straight up and away. The motherboard is the next part to be removed. This model has 2 screws fastening the motherboard to the case as shown in the picture. There are 2 more photos following, which show close-ups of each screw to avoid any confusion. They are shown by red arrows in the photographs. But, unlike previous screws, they do not have a convenient circled letter next to them.
* For this model, these are the only screws that need to be removed on the motherboard! There are other screws which may look as though they need to be removed, such as the ones by the processor or fan but these should not be removed. Remember to check the next 2 pictures first. The screw on the right. The screw on the left.
The motherboard is now released from the bottom of the case and the unit is placed in its normal position on a flat surface. Applying a steady gentle lifting force under the middle fore section of the motherboard causes it to swing up.
And then it can be lifted straight up and away from the bottom of the unit's case.
Step Three Reorienting things just a tad. In order to clear the password on the chip, some of the laptop must be put back together. This is because the laptop will need to be powered on during the process. Seeing how easy it was to disassemble, this is not a difficult task. This page shows how this part of the procedure is done, and the next page is where the real action of actually clearing the password takes place. First the display screen must be put back on.
Up to this point we have something that looks like this: Now the palmrest is be put back on.
The video connector is plugged back in. And the palmrest connector is also plugged back in.
The keyboard is also reconnected. The smaller Keyboard cable is slid back into its connector, and is held fast by closing the connector as shown is this picture. The larger cable is then gently pushed back onto its connector.
And finally, this one screw is used to hold the keyboard in place while the work of clearing the password is performed. Now the laptop is ready to and there is free access to the password chip which is located on the bottom of the motherboard.
Now, you are probably thinking to yourself 'Wait a minute! I just put almost the entire laptop back together! The wascally wabbits that made this thing sure made it difficult to get to that chip!' OK, so, you're probably not thinking the part about 'Wascally Wabbits'; but, yes, this is somewhat of a study in redundancy. The good news is that it's almost done. Nothing more has to be bought, soldered, or disassembled. Culmination Actually doing the deed. This is the page that you all came here for.
The paperclip is then unbent and, stripped of its paper-clipping function, is reformed into a totally new implement which looks like this: Next, the location of the actual chip is sought out. It is located here on this particular model.
A closer look. And the best shot I could take showing its location.
Now that the chip has been located, a closer look must be taken at the actual chip itself. This is both because this procedure will involve working rather closely with certain leads / legs on the chip, and because the correct identification of the chip in question should be verified before anything further is done. Also if this particular model of laptop is different from that may be being worked on, the chip may be in another location and a good view of what it looks like will aid in being able to find it.
You can use the direction of the writing and / or the location of the small indented spot shown in the bottom left hand corner of each chip to identify which pins / leads need to be jumped in order to clear the chip. The paperclip will be used to jump (or make a temporary electrical connection) between these 2 pins of the chip, as shown here: You should be able to see that these are the same 2 pins which were indicated by red arrows in the previous pictures of the chips.
The laptop will turn on, and a screen like this should appear. Fn-X may be pressed if desired. Also, setup may be entered by pressing F2. And the paperclip, if it hasn't already been removed, should be. It is now possible to enter setup and change all the values.
Also note that all system passwords have been cleared. But you can not use the password feature anymore, because the chip has been cleared of its information. This seems to be another not very well thought through security feature. The next page will show how the chip can be reprogrammed to allow the password feature to be used, if so desired. * Hard disk drive passwords are not cleared or removed by this procedure.
Afterwards So, now you want your own password. This page will show how a new password can be set and everything returned to normal. Now that the laptop has been cleared of the password, the primary and administrative password fields in setup both show disabled. But, on the right side of this screen, it can be seen that the option to set either of these password has been removed, due to the lack of a Service Tag. So, now you want to set your own password for the laptop.
It also contained 3 other pieces of information, which are referred to as 'Tags.' * As far as I know, these tags are only used for dell laptops. The Service Tag is a combination of letters and numbers that uniquely identify a particular computer, somewhat like a serial number. It is used by Dell technical support to be able to identify a particular computer when someone calls them. This tag is a 7 letter field.
Remember, this can only be done once without clearing the chip again. Once the Service Tag is in place, the BIOS setup can be entered, and a primary and / or administrative password can be set. That pretty much wraps it up. If you are not thoroughly bored by now, you can read the last page. It has some information about the chip that you really don't need to know. (Unless you actually need a new chip for some reason.
The CD or DVD drive is removed by pulling on this handle (which may be held in by a screw.) The hard drive cover is locked in place by a double locking mechanism. First a screw is removed from the hard drive cover. Second, the cover is slid towards the bottom slightly, both unlocking it and creating a handle, by which it can be pulled out of the laptop.
Removing the hard drive will prevent any erroneous information that may develop while working with the chip from causing a password to appear on the hard drive, or from changing an already known hard drive password. Next the keyboard is lifted up from the corner, pulled up and off, and laid to the side. It is not necessary to remove the keyboard completely.
(However if working conditions require it, it is possible to remove the entire keyboard by disconnecting 2 ribbon cables that plug into the main circuit board.) The power button/LED display panel is then removed by gently popping it up on both sides, and lifting it off.
From here the chip may be accessed in somewhat cramped conditions if further disassembly is not considered prudent. (Further disassembly shown farther down the page.) (The preceding 2 photos not taken by me) A few helpful people have sent in these pictures to assist in finding the chip on this model. Once the keyboard and CD-Rom unit are removed, the chip can be seen located just under the lip of a piece of metal which is part of the cage that the CD-Rom slips into.
The blue arrows indicate screws that must be removed. The red arrows indicate the location of latches holding the cage onto the motherboard which are carefully pried slightly sideways to free them. (As shown below.
The cage can then be lifted up like this... and then finally pulled out, revealing the chip The following 2 pictures show the location of the chip.
As show here, the chip can easily be accessed and jumped. This arrangement also offers the best chances for removal and replacement. (Actual chip may look different. This picture simply shows the proper orientation.) In order to turn the laptop on while jumping the chip with a paper clip; the power circuit board must be replaced, and the cover as well. If red don´t work, try purple pins.
Latitude C400 Short circuit the the marked pins red or purple on 24c02 during booting. If this don´t work, short direct after you pushed power. If this don´t work at first time, try it again and again.
Latitude C600 / Inspiron 4000 The Chip is on the bottom side of motherboard, under the PCMCIA card slots. Short circuit the 24C02 chip during booting.
Latitude C610 / Inspiron 4100 The chip is located on the underside of the laptop. (the bottom) It can be accessed by removing the RAM memory cover, and is located just under the lip of the plastic case. This chip should be able to be cleared by reaching a bent paperclip at an angle under the edge of the plastic lip of the case in such a way as to connect the 2 proper pins. Short circuit the the marked pins on 24c02 during booting. If this don´t work, short direct after you pushed power.
Latitude C640 /C540 Inspiron 4150 The Chip 24c02 24c04 or 24c05 is on the bottom of the motherboard just to the left of DIMM 1. Short the marked pins direktly after you pushed the power button.
Inspiron 8500 / 8600 / Latitude D800 Precision M60 The chip (24u04) is located on top of the motherboard under the hard-drive caddy approx 50mm in from the headphone socket on the left side of the laptop. Short circuit the chip during booting and start again without paper clip. Now you get the Fn-X screen. Or Short circuit the 24u04 chip during booting and release when the cursor at the display flashes.
Latitude D400 Short circuit the 24c04 or 24c05 during booting
Latitude D410 Chip is next to WLAN modul.
Latitude D500 / D505 Latitude D510 Short circuit the 24c04 or 24c05 during booting and release when the cursor at the display flashes. If this don´t work, short direct after you pushed power and release when the cursor at the display flashes. If this don´t work at first time, try it again and again.
Latitude D600 / Inspiron 600m Take out the hdd. Short circuit the 24c04 or 24c05 during booting and release when the cursor at the display flashes. If this don´t work, short direct after you pushed power and release when the cursor at the display flashes. If this don´t work at first time, try it again and again.
Latitude D610 Chip 24c04 or 24c05 is beside modem compartment at the backside. Short pin 3 and 7 wile booting. Sorry for the bad Photo. If you have an other Chip, try to short the other positions.
Latitude D810 Take out the hdd. Short circuit the 24c04 during booting.
Inspiron 3500 Short circuit the 24c164 chip during booting. If this doesn’t work, desolder the backup battery and waited 30 min and it erased the chip password. Inspiron 1100/5100 24c168 or 24c164 Chip is on the bottom of the board near the B ram connector. Short circuit the red marked legs during booting. When Password is cleared, and it´s back again after starting again, Try it again and again. If this don´t work, bridge must be left on the Chip. Some I tested work without bridge, and some need it.
Inspiron 1200/2200/ Latitude 110L Short the 24C04 while booting. If the red jumper don´t work because it´s a different chip, try the other short positions.
Inspiron XPS Gen2 / M170 / 9300 The chip (C24O4N) is located on the bottem of the laptop right next to the two DIMM slots. short the pins (3 and 7) IMMEDIATELY AFTER hitting the power button.
Latitude X1 Short the 24C04N while booting.
Latitude CPIA The chip on this model is located under the processor itself. The only method I have been told of, (as I have not had a chance to work on one of these models myself) is by soldering or otherwise attaching 2 small wires (insulated or covered wires) to the leads / legs of the chip. Then running them out of the laptop where they can be connected after the laptop is turned on. And replacing the processor very carefully.
Latitude CPIx Latitude CPX
Latitude L400 As you can see from the above picture, the Latitude L400 comes in a thin leather case. It is quite stylish, save for the fact that the Dell logo is emblazoned on the front and on the zipper pull tabs. The L400 Also comes standard with a 20 GB Hard drive and 256 MB of RAM. And this one came with Windows 2000 Professional, as I found out once I removed the password. But, enough about the way it could work, let's get on to how to get it working again if you are locked out of it by a password.
A password screen locks us out of the laptop. But not to be defeated, we just get out our tools. This laptop is rather easy, and only requires the removal of 4 screws, and doesn't even need a paperclip. This one can be cleared by removing power to the CMOS or BIOS chip. This laptop does have a 24C02 chip on the back of the motherboard. (I took it all the way apart; in order to get to the chip, almost every single screw in the whole unit has to be removed.
This slide plate just above the keyboard needs to be pushed towards the left. It may help to lift up on the right side slightly while pushing it to the left. It slides about ½ of an inch to the left and then can be pulled off. Now, removing the slide plate reveals the 4 screws that hold the keyboard in place. (The red arrows indicate which screws are the ones that need to be taken out.) The Keyboard needs to be lifted from the front, and pulled towards the screen slightly.
Now the single keyboard connector is removed and the keyboard is pulled off the unit. This connector is one of the ones that can be taken off and replaced easily. Here you can see the actual BIOS chip itself (yellow arrow), and the CMOS battery (blue arrow) that we need to remove. The CMOS Battery powers the CMOS/BIOS chip, giving it power to hold the settings and passwords and such while the laptop has no power.
The CMOS battery is held onto the motherboard by a sticky glue. A flat tipped screwdriver or other prying device is used to gently pry it upwards until it is loose. Finally the CMOS battery plug is pulled loose from its connector socket on the motherboard.
The pernicious CMOS battery is held victoriously. This is it. The final, last part of clearing this laptop. After waiting about five minutes, it can be replaced and everything put back in place. The password is now cleared. When the laptop is put back together, it is important to slide this corner of the keyboard in just right.
Extraneous Some unnecessary information about the chip. This page is dedicated to somewhat trivial information about the 24C02 non-volatile RAM chip that is used to store the passwords and tags which was the focus of this site.
I have seen and heard about people who offer to sell new blank 24C02 chips to people, so they can unsolder their old one, and then re-solder the new one in. This will work, if all goes well and the new chip has not been damaged. These people, and their websites, attempt to convince anyone needing to clear a password on particular laptop models that they have only one recourse.
and then hoping that it works. Now, if someone really does need a chip, (If this pertains to you, I'll bet you wish you hadn't been so hasty) one can obviously be ordered from a reputable business. But, this may not be necessary! The 24C02 and related / compatible chips are all around you. If you work with computers, then they are right under your nose. If you have a DIMM memory module available, look at what it says on the small chip in the upper right hand corner.
I saw one on a DVD decoder card, (hmm...) and I heard about a similar chip (24C16) being in a satellite receiver box. (I wonder what they could be doing in such devices.) (Not to mention that many smart cards [like the ones that go in satellite boxes] have a 24c02 or similar chip embedded inside of them) I don't know for sure, but I'm guessing that; the modem uses the chip for manufacturer, speed, and Plug and Play information; and the LAN card for PnP and / or NIC number.
The information in the chip can be read / written with a special device called an EEPROM reader or programmer; or a PICprog (Programable Integrated Circuit programmer.) Devices like these can be purchased for around $100 or less, and [with a some time and quite a bit of reading for those new to electronics or programming] used to read, write, or manipulate the information in EEPROM chips.
