reg vardy?its considered to be a renault part but if it happens to be a electric problem its down to nissan to sort it out, i would do what i have done several times take it in get it fixed and take the keys say the check is in the post customer service wont help you unless you dig your heels in the ground ring nissan assist its like customer care but its the head one they will (should)send out a rac blokey to fix it for free the number is 0800246820 not many people know this number but they are very nice on the phone tell them that you need to see out your mirror because you drive on the motorway a lot that should work :O) hope that helps , let us all know 
wing mirrors are covered as its not an interior part , go to a different nissan dealer ,any nissan dealer can fix it if its under warranty it dosent have to be the one you bought it from, also tell him hes speaking tosh and ask to speak to his senior, on the other hand if its been hit in any way the cost is down to you,get nissan to send you an email stating that it has not been declined and shove it up his you know where lol (exhaust pipe? lol)
