Touch screen is on but unresponsive

Ben,

Thanks for the reply. What you say bears out my experience! I have found that the flat cables for the touch screen/digitizer are very easily damaged! I've managed to do it twice. The first time was due to me just not understanding the need to ensure that they are carefully handled and fully extended as they are tucked through the body of the phone and the screen/digitizer is eased into place. It is so easy to trap it or kink them and the tiniest kink will shorten it (so it won't then reach its plug-in destination later in the rebuild ) and the lightest tug will rip it. On the second occasion, I was so careful! However, it appears that something is wrong. It may be the in the manufacture of the screen/digitizer but I've no real way of testing it, other than putting into my phone.

My iPhone 4 is well out of warranty now so to fix it would mean either me having a third go or sending it away. I've probably spent more on parts than it would have cost to send it away now! I've learnt some lessons for this repair which are:

• Treat the two ribbon cables on the screen/digitizer with extreme care, even as they are taken out of the delivery packaging. The thinner one is the real monkey, which has to be extended the furthest and can be ripped as easily as aluminium cooking foil.
• Very gently ensure that the ribbon cables are extended fully and without being trapped or kinked as the screen/digitizer is put into place and as they are passed through the phone case. You can't pull them through later once the six side screws and four corner screws are in place.
• Best to buy your parts from a recognised and reputable source.
• The repair is possible but set aside some time (several hours if it's the first time) and don't try and rush it.
• Weigh up if you really want to do it (It's quite fiddly but logical) or if your main objective is just to get a working phone at a reasonable price. Compare parts prices with a send-away service!