william29 wrote:
Just to be clear, you definitely can phone numbers with non-iPhone iOS devices and Macs that do not have cell service. I routinely get iMessages sent to my phone number that show up on all of my non-iPhone iOS devices and my Macs.
I understand this is possible. That was not the question the OP had asked. He was trying to use an iPhone without wireless service. While the support document that I provided gives instructions on how to activate iMessage for that device, he is trying to use the phone number from his active device on that non-active device.
The question really relates only to an iPhone that no longer has cell service and whether iPhone iOS is different in requiring the successful send of an SMS message for activation of iMessaging. This is clearly not the case for non-iPhone iOS devices or Macs.
Again, he can activate iMessage on that device with the Apple ID, but I do not believe he can associate the Phone number from his active device on that device. Although, as I think of it, there is a support document, that I cannot locate right now, that allows you to add a phone number to use with a Mac computer, so it might be able to be done with the iPhone without cellular service. I guess they could search the support site for that document.