Battery problem for Iphone 4
FYI I am not aware that Apple has anything at diagnostics.apple.com or diagnosis.apple.com. 

For troubleshooting help with iPhones you can go to 

http://www.apple.com/support/iphone/ 

...or fill us in on exactly what your problem is, step by step. Please be as specific as possible: "my iPhone won't turn on" or "my iphone will naot make a phone call" etc...