How to disassemble Dell Inspiron 15 3521/5521

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Dell Inspiron R15-5521/3512 disassembly

In this guide I explain how to disassemble a Dell Inspiron 15 3521/5521.

I will remove all main components from the laptop and show how to access the cooling fan.

You can use these instructions for replacing failed internal components or cleaning up the heatsink and fan.

Before you start taking it apart make sure the computer is turned off.

As always, I advice to keep track of all removed screws. Make notes. It will help you during the reassembly process.


Unlock and remove the battery.

Remove laptop battery


Loosen two screws securing the service cover on the bottom.

Lift up and remove the service cover. You’ll have to apply some reasonable force to remove the service cover.

Loosen screws on service cover


Now you can access the hard drive, both memory modules and CMOS battery.

Hard drive and memory access


Remove two screws securing the hard drive to the case.

Remove screws from hard drive


Pull the hard drive to the left to disconnect it from the motherboard.

Disconnect hard drive


Now lift up the hard drive and remove it.

Remove hard drive


You’ll find five latches securing the keyboard on the top.

By the way, in order to remove the keyboard you don’t have to go though the previous steps. Just follow STEP 7-STEP 13.

Keyboard latches


Those latches are spring loaded.

Push on the latch using a small flathead screwdriver. The latch will move inside the case.

Push keyboard latch inside

At the same time, while the latch is hidden inside, insert a sharp object under the keyboard and lift it up a little bit.

This will not allow the latch to lock the keyboard.

Do the same with all remaining latches.

Lift up keyboard


When all five latches unlocked, you should be able to lift up the keyboard and separate it from the top cover assembly.

Besides five latches on the top, there are two plastic retainers on the left and right side of the keyboard.

You’ll have to apply some reasonable force to move the keyboard though those ┬áretainers on both sides.

Lift it up and move towards the display assembly.

Slide keyboard towards display assembly

STEP 10.

Turn the keyboard upside down.

Now you can access the keyboard cable connector on the motherboard.

Before you release the cable you’ll have to unlock the connector.

Keyboard connector

STEP 11.

Lift up the left side of the connector retainer with your fingernail.

The retainer will open up at a 90 degree angle.

The retainer (brown) must remain attached to the connector base (white).

Unlock keyboard connector

STEP 12.

On the following picture the connector shown in the unlocked position.

As you see, the retainer is still attached to the base.

Now you can pull the keyboard cable from the connector.

Unplug keyboard cable

STEP 13.

Lift up and remove the keyboard.

Remove laptop keyboard

STEP 14.

Remove all screws from the bottom.

Remove screws from bottom of laptop

STEP 15.

Remove screws securing the top cover (palmrest) assembly.

Disconnect the power button board cable and trackpad cable from the motherboard.

Use same technique as for disconnecting the keyboard cable.

Remove screws securing top cover

Lift up the cable retainer.

Disconnect power button board cable

Pull the cable from the connector.

Disconnect power button board cable

STEP 16.

Now you can start separating the top cover (palmrest) assembly from the bottom cover.

I’m using the guitar pick for that. You can use a piece of plastic.

Separate top cover from bottom cover

STEP 17.

Continue separating the top cover from the bottom cover.

You’ll have to apply some reasonable force to separate these two parts. There are hidden latches securing them.

Continue removing top cover

STEP 18.

Remove the top cover (palmrest) assembly.

Remove top cover assembly

STEP 19.

Here’s the bottom side of the top cover (palmrest) assembly.

Here you can access the trackpad, trackpad button board and power button board.

Bottom side of top cover assembly

STEP 20.

Before removing the motherboard it’s necessary to disconnect and remove the wireless card.

Wireless card

STEP 21.

You’ll have to disconnect two antenna cables, remove one screw securing the wireless card and pull the card from the slot.

Wireless card antenna cables

Here’s how to disconnect the antenna cable from the wireless card.

Simply lift up the cable form the card by the gold connector.

Disconnect antenna cable from wireless card

STEP 22.

Remove one screw securing the motherboard.

Disconnect the following cables:
1. Video cable.
2. DC jack cable.
3. Speaker cable.
4. I/O board cable.

Disconnect cables from motherboard

Here’s how to unplug the video cable.

Disconnect video cable

And DC jack cable.

Disconnect DC jack cable

STEP 23.

Start removing the motherboard from the laptop case as it shown on the following picture.

Lift up motherboard

STEP 24.

Remove the motherboard.

Remove motherboard

STEP 25.

You can access the cooling module (heatsink and fan) on the other side of the motherboard.

Other side of motherboard

STEP 26.

In order to remove and replace the fan you’ll have to disconnect the fan cable and remove one screw.

When the cooling fan removed you can clean up the fan and heatsink.

Disconnect cooling fan

Here’s the bottom cover of the laptop with the motherboard removed.

Bottom case without motherboard

The DC power jack located in the upper left corner of the bottom case.

DC power jack

Here’s the official Dell Inspiron 15 3521/5521 owner’s manual. This manual also has detailed disassembly instructions.

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12 Responses

  1. Brandon

    Hi, I am locked out of my laptop via bios password that has been lost. It is the same as this laptop Dell inspiron 15-3521. Do you by chance know a master password for this computer in case of a situation like this? I have tried the keygens on the net but to no avail. I will gladly donate for your assistance…thanks

  2. IML Tech

    @ Brandon,
    Sorry, cannot help with the BIOS password.

  3. Balsey Dean De Witt, Jr.

    Disconnect the power cord and remove the battery.

    Remove the access door on the back of the computer, two screws hold it on.

    To the left, as above in the photo’s, you will see the bios watch battery. Remove it.

    Turn laptop over and press the power button and hold for 10 seconds.

    Turn laptop over and install the watch battery.

    Finish up hooking up the rest. This should remove the password that was given to bios.

    Good luck. This used to work in the old days, not sure of today, but you would think it would.

  4. Rodrigo

    Hi! I accidentally dropped my laptop and it got dented on the lid, next to the DELL logo. I want to take the lid off so I can punch the dent back, but I have no clue on how to do that without messing up the touch screen. Can you help me please? I’m desperate!

  5. hey i think this helped me unscrew my laptop…thanks a lot.

  6. Hi I am Currently using this laptop can i upgrade new graphic card to 1 or 2 gb ..? plz reply ..!

  7. August Tiamzon

    Hi, I changed my LCD screen on my dell 15r 5521. After doing this. It has no power or any light on my laptop. What should I do?


  8. Noah Beck

    Hey I got this laptop of craigslist and it’s a dell inspiron 15-3521 but the power button is broken an I just wanted to know if you knew of a way to turn it on without having to go through all the trouble fixing the power button etc… If you know a way that’d be awesome thanks (I do not have a warranty)

  9. IML Tech

    @ Noah Beck,
    Sorry cannot help with that. Probably you can do that but I don’t know the pinout.
    By the way, you can buy a replacement power button for this laptop on eBay. It’s only about $4 with free shipping.

  10. samuel ola

    my dell mother board is retuning current, when i plugged charger to it the charger will went off please any suggestion or what may be the course of it

  11. IML Tech

    @ samuel ola,
    I don’t fix motherboard on the component level but it sounds like there is a problem with the DC jack or the motherboard itself failed.

  12. Do you know how to replace the audio jack on one of these?

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