I looked, doesn't mention anywhere in the warranty manual that electrical work is excluded or only warrantied for 1 year.
I will go look at mine and see what it says. I know there are many things that are 1yr 25k - I asked specifically for a list as I had a few issues that Nissan denied warranty, one being the ground wire dry rotted after 18 months into the ECM for the fuel evap. Another was my front rotors warping with just over 25k and the dealer covered it (told a little white lie on the mileage) and I have never used OE rotors again.
I fought Nissan Canada regarding ECM wires rotting, as they stuck me with a $800 bill, which I told them to stick it somewhere sideways. After many calls trying to talk to someone other than the parrots that first answer the phone, and after weeks of review, Nissan finally decided to cover 1/2 the bill (the dealer knocked it down to $600 from $800 as they performed the work without prior permission, which I requested). So, I waited for my cheque to arrive - that took a while, then I cashed it, waited a few more weeks and then called Nissan Canada back. Got to talk to the same fine gentleman regarding the crumbling harness after 18 months and told them that now that they have admitted culpability for an inferior product and paid half of the bill, I would like them to now pay the other half. Needless to say, that wasn't well received, but through patient talking and reasoning they finally agreed to pay the other half as long as I agreed to not press any further electrical issues and acknowledge that the warranty was over.
But you don;t need to believe me, why not ask Nissan directly? Ask them for a detailed list of what is warrantied and what is not.