I'm in the market for a new XLS and I can't locate the color and options I want. I found a car with everything except the Nav and am considering having it retrofitted (either by myself or the dealer). Is it all plug and play with existing harnesses and adapters or am I better off just going the distance and finding one that already has the Nav?

 

I'd wager to say it's likely easier to add an aftermarket nav than the factory one, but I haven't done a ton of research. If the FUSE and such are external modules that just talk on the data network, then it should be a piece of cake.

I would say if you can find one with the nav in the trim and color you want that's a better choice though, as it eliminates any possible finger pointing for warranty issues.

 

Its very easy. You need the actual NAV plus the install kit (which has stuff like the bezel).
I would say about an hour of work if you take it slow.