[8125, K-JAM, P4300, MDA Vario General] veda_sticks:
I have the same problem, i cracked the touch screen part and the lcd was fine, i then discovered on dismantling that the touchscreen part is glued to the lcd assembly, managed to prise it of using a knife, then discovered that the ribbon strip is soldered, i also discovered that the ribbon on the replacment touchscreen does not align properly with the board, the middle ones line up fine but the outside strips are slightly to far apart, i managed to tape it in position but it does not work. Im gonna take it apart again and check that i have the screen the right way around, if that fails, i am gonna get some thin wires to solder onto the ribbon then to the board, i will report back if this works.

I too will recommend replacing the lcd/touchscreen as a complete unit, however if this works for me and u are confident with soldering then go ahead. (please not though that a new lcd touch unit goes for upto £80, touch screen itself £12)J

The manual is a god send as every step for my t-mobile mda vario was pretty much correct for dismantle, and ithe manual even includes re assembly.

Update:

Ok so i dismantled my mda vario again, and tried to make the 2 outside strips on the ribbon make contact by using wire to make a bridge from the contacts on the board to the ribbon, the 2 middle strips contacted fine, after taping the ribbon down and reasembling touch screen still does not work. I did notice however that my replacement touch screen that i got from ebay doesnt feel the same as the original, when u press the stylus on the screen it feels solid plastic rather than a sheet of pliable plastic thats over the top of the glass like the original. Im gonna have another attempt with it once i get fitting for my soldering iron that is fine enough to solder.

The other thing i noticed is, i looked on ebay again and there is actually 2 touchscreens listed for this phone, which have to slightly different ribbon strips, the one that i have which the strips dont line up properly, and from the photo on ebay there is another that looks like they are closer together.

http://cgi.ebay.co.uk/LCD-TOUCH-SCR...ryZ41343QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

this is the one that i have, notice the tracks on this ribbon strip

http://cgi.ebay.co.uk/I098-Touch-Sc...oryZ3728QQrdZ1QQssPageNameZWD1VQQcmdZViewItem

Now this one has a slightly different ribbon that looks as if it may line up properly.

If soldering the touchscreen on still does not work and i am certian that the contacts are defnatly good with no bridging, i may consider trying the 2nd one, but i will make equiries to the sellers to see if they have any fitting instructions.

I am hoping i can get this working as it really dont want to have to pay £80 to get the lcd + touchscreen. The touchcreen itself can be bought for £12 including postage from ebay.

Dismantling the phone is actually not that difficult and once u have done it once, the next time is pretty easy.

Just be carefull not to loose the screws, they are very small and easily bounce out of sight.

So, as a wee reminder, if u are wondering on how your touch screen is removed, it is glued in position ontop of the lcd. To remove, use a thin sharp knife on on of the corners to chip away at the glass (dont worry its not part of the lcd just be carefull as the touchscreen glass sits pretty close to the actually lcd display) until u can get the point of the glass under it and break it away ppeice by piece. The new touch screen can be placed on top once all shards of glass have been carefully cleaned off. The surface will still be a little sticky but not much. It should keep the screen in place for reasembly.

Will hopefully get this working soon.