Question about key/remote and ignition

[sw20>>s14]

I recently bought my M45 used and it only came with one remote. I shrugged it off at the dealership, but later on found out what a nightmare it is for 2003-2004 M45s owners (and F50 owners) that need extra remotes (both price and reprogramming). I ended up buying a used ignition from a dismantler that came with a matching remote. I really only wanted the remote, but figured having an extra ignition switch never hurts.

I called my local Infiniti service department and asked if the ignition would still be useable after I reprogram the remote. He wasn't 100% sure, but assumed the ignition would be useless afterwards since the codes will no longer match. I'm not too savvy with these remotes and the security system, but will the ignition be rendered useless if I reprogram the remote it came with?

[The00Dustin]

I don't know about the 2003-2004 M45 specifically, but I've never seen a programmable remote. Generally, you reprogram the car. Moreover, the reps that talk to you at the local service department are definitely not automotive technicians. Lastly, I can't imagine why the ignition switch would be useless afterwards, as I also doubt that it has anything to do with the programming, but even if it has a programmable module, I see no reason why it couldn't be reprogrammed and/or why the car couldn't be reprogrammed to match it if the one in the car failed.

[EdBwoy]

As he said above, the ignition will not be rendered useless. For now, your car will be programmed afresh to accept your old key as well as your new key.
If for some reason, you need to install the new ignition in your car, then the car will need to be programmed to accept the new ignition module and the 2 keys. Only difference will be the traditional blade insert, which we don't get to use frequently.