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.
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.
Now you can access the hard drive, both memory modules and CMOS battery.
Remove two screws securing the hard drive to the case.
Pull the hard drive to the left to disconnect it from the motherboard.
Now lift up the hard drive and remove it.
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.
Those latches are spring loaded.
Push on the latch using a small flathead screwdriver. The latch will move inside the case.
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.
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 retainers on both sides.
Lift it up and move towards the display assembly.
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.
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).
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.
Lift up and remove the keyboard.
Remove all screws from the bottom.
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.
Lift up the cable retainer.
Pull the cable from the connector.
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.
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.
Remove the top cover (palmrest) assembly.
Here’s the bottom side of the top cover (palmrest) assembly.
Here you can access the trackpad, trackpad button board and power button board.
Before removing the motherboard it’s necessary to disconnect and remove the wireless card.
You’ll have to disconnect two antenna cables, remove one screw securing the wireless card and pull the card from the slot.
Here’s how to disconnect the antenna cable from the wireless card.
Simply lift up the cable form the card by the gold connector.
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.
Here’s how to unplug the video cable.
And DC jack cable.
Start removing the motherboard from the laptop case as it shown on the following picture.
Remove the motherboard.
You can access the cooling module (heatsink and fan) on the other side of the motherboard.
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.
Here’s the bottom cover of the laptop with the motherboard removed.
The DC power jack located in the upper left corner of the bottom case.
Here’s the official Dell Inspiron 15 3521/5521 owner’s manual. This manual also has detailed disassembly instructions.