Generally speaking, if the construction was up to code at the time it was built (and assuming no alterations in the interim), the owner does not need to bring the item up to current code. However, without knowing exactly what the city inspector found, it is hard to say in your specific situation.
Frank W. Chen has been licensed to practice law in California since 1988. The information presented here is general in nature and is not intended, nor should be construed, as legal advice for a particular case. This Avvo.com posting does not create any attorney-client relationship with the author. For specific advice about your particular situation, please consult with your own attorney.
A agree with Attorney Chen. I would only add that something else sounds fishy here. Sometimes you can be required to upgrade your property, but there must be a triggering event. For instance, if you pull a permit to do some electrical work, you might be forced to upgrade a bunch of things you didn't plan on upgrading. What I have never seen is a situation where a neighbor brings in an inspector for something not on their property, unless its for illegal upgrades, etc. I recommend retaining local real estate counsel. The Parker Law Group is an excellent real estate firm right in your area. Good luck.
At first, I was going to respond that as long as nothing changed since the installation and it was up to code at that time, the City could not force you to bring it up to code now.
But, in one of your comments you mentioned something about removing some hardscape. If you did that, the City could now force you to bring it up to the current code.
Without knowing a lot more, you probably cannot get a complete answer on the AVVO site.
If the City is wrong in forcing you to bring the property into compliance, you will have an opportunity to respond. You should consult with a construction or real property attorney to make sure your rights are protected.