It varies from generation to generation of iphone as the 3GS motor used to be very easy but getting at the 5S motor was a lot more work and much more scope for things to go wrong so well done at least getting that far, reassembling then testing although I know from experience putting a iphone back together after a "fix" then testing and realising its not fixed is quite demoralising given the time it takes.
I guess it could be a software issue that may be resolved with a hardware reset and/or restore using itunes as I have had a few issue in the past I assumed were hardware that have been resolved by a reset and restore (muck like Windows issues often go away with a clean install)
I took the 5S apart again yesterday evening and very carefully aligned the vibration motor with the two contacts. It works now.
Really weird it needs this kind of precision as the phone is supposed to be assembled by no-skill labor.
To be honest while I haven't replaced a 5S battery yet, it seems easier to work on than a 4S. The screen is removed in a matter of minutes without having to dismantle the phone and the vibraton motor is right there, three screws and it's gone.
Kermit Messages: 23109 Registered: June 2003 Location: Yorkshire
(22) Giacomo Agostini
Agree some things easier on some models than others. I seem to recall on 3GSs something like a screen replacement (which is a common fix) as a pain the arse as the back comes off first and you have to remove everyhting to get the screen. 4S iirc was similar. With 5S onwards, its the screen that comes off first so easier to fix that.
Not sure if its no-skill labour assembly or mainly that each person (or robot for many stages) has a specfic and simple task before a phone moves along the assembly line meaning. It really only gets tricky when like we do at home have to perform lots of these one after another adding to complexity.