Check/training/aircraft has a tech issue?
All are missing the point of why it is a bad idea - the profile of the NPA/2D approach may be significantly different from the ILS, so you end up with conflicting information. Fly the approach you are flying!
ATC are in the process of switching the ILS on....
? If it is not yet on then having the ISIS diplaying will not do anything, and if it is then why not wait 3 minutes and fly the ILS?
I fully get wanting to know what it will do for nerdy reasons, I'm right there with that one!