I'm going to buck everything you read on google about it being your flex cable and say it's probably your home button spring. That spring gets compressed and needs to be pulled up a bit so it can once again make contact with the home button circuit.
The diagram for the home button is like this: http://imageshack.us/photo/my-images/215/homebuttons.jpg/ In that image when the digitizer is in place 1 and 2 are in contact with each other and 3 and 4 are in contact with each other. The button just completes the final connection.
If you have a multimeter to check for continuity, you can press the home button on the digitizer and see if points 1 and 3 give you a "ring".
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If it really is you flex cable then you can find one [http://www.ebay.com/sch/i.html?_nkw=ipod+home+button+3rd+gen+flex+cable&_sacat=0&_sop=1&_odkw=ipod+home+button+3rd+gen&_osacat=0&_trksid=p3286.c0.m270.l1313|on ebay.]
I'm going to buck everything you read on google about it being your flex cable and say it's probably your home button spring. That spring gets compressed and needs to be pulled up a bit so it can once again make contact with the home button circuit.
The diagram for the home button is like this: http://imageshack.us/photo/my-images/215/homebuttons.jpg/ In that image when the digitizer is in place 1 and 2 are in contact with each other and 3 and 4 are in contact with each other. The button just completes the final connection.
If you have a multimeter to check for continuity, you can press the home button on the digitizer and see if points 1 and 3 give you a "ring".