Today's fix is real easy and depending on what tools you got, will probably take you between 10 to 15 minutes. It has to do with malfunctioning keypads. Generally, when a cell phone's keypad is not working properly it could be one of three different reasons:
1- Due to shock from a drop, circuitry is damaged thus no matter how hard you press you will never get the phone to register it. This issue is one that a certified technician would have to take care of and is nothing that we can fix here as it would be time consuming and expensive.
2- Because of moisture or heat, again, the circuitry could be damaged. Nothing to be done here really. The only thing to try best for a phone that's been subjected to moisture is to place it in a sealed container with rice. The rice will draw out the moisture and if there was not too much damage the phone should work fine. Click here to see a great Instructable that demonstrates this principle. Thank you keegsta123
3- The phone's keypad membrane is broken or dented. This is where we come in and fix the problem. Now keep in mind, the keypad membrane and the keypad itself are two different components; this is true for most models of cell phones, though there are exceptions. While the actual keypad is comprised of the buttons you press, the keypad membrane is what allows the keypad to register a touch to the circuit board (it is basically a thin, white, plasticated film with small metal sections of a hemisphere that act like mini Pogs). We will see what these look like and how it works later in the Instructable. Now on to the first step!
Step 1: Find the Phone
Go ahead and turn over the phone, remove the back cover and set this aside. Then turn the phone over again to the front.
Step 2: Phone Facelift...literally
Once you have this off, the keypad should easily come off as well. Take these three parts and put them off to the side for now. Be gentle as some of the shells will be fragile and all of them should have a clear plastic cover that fits over the screen to protect it from dust, and other particles that might scratch it.
Step 3: Disassemble
Cellphone screws will vary in what kind of screwdriver fitting they take. In my case, it took a torque screw fitting which was a little hard to find. That's where the Squirt Lethearman tool came in handy. Some others will even use mini phillips head fittings but whatever the fit, make sure you do not strip the screw, otherwise you will have a very hard time putting it back on, or taking it off at all; the Leathearman tool won't help you here since I tried on one of my Samsungs and the fitting was still too small.
Once you remove the screws I would advise putting these inside the faceplate so that you don't lose them.
Step 4: You Gotta Keep 'Em Separated...
The metal speaker housing.
The clear, plastic screen housing.
The actual screen itself.
The keypad membrane.
As far as all the first three components are concerned you don't need these at all right now, other than for purposes of admiring their construction. In fact you can even leave the speaker housing and screen housing together with the screen sandwiched in between.
Step 5: Let's Go Back to the 90's for a Sec...
The way the little metal Pogs work is that they sit on top of the little golden circles corresponding to each key. They are slightly larger so they don't make a connection. When you press a key, what happens is that the little bump in the actual keypad push the Pogs on the mebrane down. This creates a connection between the metal in the circuit board and the Pog that registers as a touch. When these little Pogs are dented as you can see here, you can press all you want but it won't make a proper connection an thus you won't be able to register a touch for that particular key.
You can do two things here:
1-Reshape the pog so that springs back whenever you press one it. To test this once you're done reshaping it. Put it back on the hard surface face down and press the corresponding Pog. In order to reshape it use a small metal screwdriver or something hard and just go around and flatten the middle but raise the sides of the individual Pog.
2- If the membrane is beyond repairing you will need to either buy one or makeshift one. This will be a really hard and precise task so if you don't want to put in that much time and effort I suggest you either get a new membrane or send it back to the company. If anything it might even be cheaper to buy a cell phone at any local Pawn shop.
I don't know where you could find an actual membrane and I've searched online but have only found obscure links to so I would try and see if your carrier's store might have a few laying around.
Step 6: The End...is Only the Beginning.
First, give your keypad membrane a cleanup if you stuck with option '1' of fixing it so it's nice and shiny. (Don't scrub too hard though.)
Second, place the screen housing, screen (make sure all the little magnifying lenses are there with it too), and speaker housing all back on top of the circuit board.
Third, screw back all the little screws.
Fourth, place the keypad down, then the faceplate (it should snap right back in place) and the battery with the backplate.
Fifth, you're done!! If you followed every step properly then you should have fixed your keypad. Congrats! Now turn it on and enjoy.
Oh and here's a freebie in the next step.
By the way guys. I have never done anything like this before. I just opened the phone up and learned as I went so if there is something broken sitting at your house, it's probably just begging to be opened and prodded. Who knows, it might be fixable and even if it isn't, it will still be a learning experience.
P.S. I just noticed the movie can't be seen unless it is downloaded. This is simply to show that the keys I fixed work. If you don't mind downloading it please do so, otherwise I am working to fix this.