N900

Step 1: Remove backplate, battery and SIM card. Removing the SIM card is optional, but I had no way of knowing it before removing the system board.



Step 2: Take out the 6 screws. The two Torx T6 secure the keypad bezel to the base, the Phillips attach the screen to the base. Gently slide the screen open, and lift it, pivoting around the edge towards closest to the keypad. The slider mechanism has a lip that hooks under the keypad bezel, pivoting the screen releases it (if you've watched the Youtube video clip disassembly, this lip makes the loud noise they mention). The screen ribbon cable should just detach from the base by lifting it with a finger nail. At this point the screen and the base are completely separate.


Step 3: Separate the screen and the GENTLY slide a finger nail along the seam between the keypad bezel and the base. I cannot stress being gentle enough, since the bezel is the flimsiest piece of plastic I've ever seen in an electronic device. If you look closely at the picture below, you'll notice it has 6 teeth that secure it in place along with the 2 Torx screws. If you're not careful, they WILL break (mine didn't, neither should yours). It should take almost to pressure to lift the lower edge. Once this edge is loose, pivot it upwards and slide the bezel off. The keypad is just sitting on top of the base.




Step 4: Hold the base as you would hold the phone normally, with the keypad towards yourself. Insert a finger nail between the upper right corner of the system board and the base. Pull the system board parallel to the base towards yourself, while also lifting that corner. At the same time release the grey clip that sits somewhere between the power button and the volume control buttons (sounds more difficult than it is). This will pry the system board from the base without any force.


Step 5: This will be a bit tricky because the bottom of the system board is secured with a lot of clips, and the camera snags the base somewhere. You don't want to start prying those clips loose because they will break. But if you carefully rotate the system board upwards away from yourself, with the camera as a pivot, there will be a point where it just slides out without forcing anything.



Step 6. Well, at this point look very carefully at the system board. You'll notice that the USB port (which we're trying to secure) is surface mounted on the system board. Given the amount of force required to insert and remove the USB cable, I'm really not surprised so many people broke theirs. You'll also notice that there is a secondary board that surrounds the camera and that is glued to the system board with sticky foam.

When the phone is fully assembled, this secondary board is pressed against the base and the system board. I figured that using epoxy to fill the gap between the USB port and this secondary board, as well as behind the USB port will more than secure it in place and prevent it from breaking off.




Step 7: I did this in 2 steps, because epoxy has a very short time when it's workable. Although I used just a regular 5 minute epoxy, after you mix it for 30 seconds you only have a couple of minutes while it's still liquid. Afterward it becomes too viscous to insert into the small spaces we're working with. In case you're wondering, regular epoxy does NOT conduct electricity, so you are in no danger of shorting anything out. Unless specially formulated, epoxy is not the best electric insulator, but we're not worried about that here, we just need it to be non-conductive.

Step 7a: Mix a small batch and insert as much epoxy as you can behind the USB port, filling the gap between it and the metallic heatsink hiding under the secondary board.
Step 7b: Mix another batch (or use the first batch if it's still liquid) and fill the gap between the USB port and the secondary board. Make sure none of the Epoxy runs into the USB port. The metal casing of the port is full of holes, and if you apply too much epoxy in this step it may run inside, rendering the port useless.

The end result should look something like this:


Step 8: Let the epoxy cure for about 30 mins, then reassemble the N900 in the exact reverse order. DO NOT OVERTORQUE the Torx screws securing the keypad bezel to the base. You WILL strip those screws if you do!!! Also, reattaching the screen ribbon should not take almost any pressure. If it does, you're not alligning it properly.


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Cosmin N.,
Feb 21, 2010, 4:00 PM
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Cosmin N.,
Feb 21, 2010, 4:01 PM
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Cosmin N.,
Feb 21, 2010, 4:02 PM
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Cosmin N.,
Feb 21, 2010, 4:03 PM
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Cosmin N.,
Feb 21, 2010, 4:05 PM
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Cosmin N.,
Feb 21, 2010, 4:05 PM
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Cosmin N.,
Feb 21, 2010, 4:05 PM
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Cosmin N.,
Feb 21, 2010, 4:05 PM
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Cosmin N.,
Feb 22, 2010, 9:36 PM
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Cosmin N.,
Feb 22, 2010, 9:37 PM
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Cosmin N.,
Feb 22, 2010, 9:38 PM
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