What has happened to my cellphone keypad?

June 12, 2007 11:31 AM

I had to replace the housing on my Sony Ericsson K750, and did so with a W800 housing I got on ebay. Now that I've done this, the 1, 2 & 3 buttons on the keypad don't respond, nor will the joystick effect down or right actions. Everything else, including the camera, works fine. What has happened, and can I fix it?

Obviously I can work-around the joystick issue, but the missing numerical buttons is certainly a problem. I've tried using the old keypad too and those buttons just do not activate.

Here's a link to the how-to site I used, if it's any help.

posted by russmail to Technology (3 answers total)

Your link looks like the short version.
Did you see these instructions? It looks like the same thing, only more details. Note the warning after removing the keypad about the brass clips.

The 1, 2 & 3 are in the same row, so this looks like it could be a connector problem. I can't find a wiring diagram, so I don't know if the joystick and the keypad share the row in some way, but it's not unlikely.

Other suggestions:
- examine the connector and socket of the key assembly carefully to see if any wires are broken or shorting.
- it looks to me like the actual keypad does not have any switches, but the backs of the keys contact the switches underneath. If so, try it with the keypad out and push the switches underneath- to see if the keypad is misaligned with the switches. The pictures show 6 switches being activated by 12 keypads, so I figure there is sharing (ie 1,2,4,5 share the upper left switch) that might make alignment more critical.
-look for places where contacts could short out (to the case, to other components) and insulate with electrical tape
posted by MtDewd at 1:07 PM on June 12, 2007

I photo-blogged myself doing this on my own blog (WARNING!!! Self Link!). I had nearly the same problems, some of the buttons were not working correctly. I solved it by tightening up the torx screws inside the housing. Then making sure I had the front facia plate in place securely.

Basically you want to make sure that it all fits together snugly. If it is at all loose then the connections inside wont be made and you will have problems like this.
posted by gergtreble at 1:15 PM on June 12, 2007

I had a K750i and the 1,2,3 button and the joystick -- and the power button -- all stopped working. I hadn't taken it apart. The buttons just stopped working. The power switch would work to turn on the phone, but once it was on, it wouldn't respond.

I took it apart and tried to find if I could find the source of the problem. Eventually I gave up and bought a K800i. I figured it was either the dunking it took into a glass of Diet Coke several months earlier finally taking its toll, or the firmware hack I had upgrade to re-regionalize and de-brand it broke it. I didn't have a Windows PC to re-flash the phone with firmware. I was thinking it might have been software because the buttons did work right at startup, it was only after the phone found a network did the top row of buttons -- and power button, stop working.

Good look.
posted by birdherder at 1:32 PM on June 12, 2007