I work for Enterprise Rent-a-Car and we've had a few (not many) problems with our 05 Altima 2.5S, same symptom as yours...SES light comes on and stays on. Usually it could be a faulty sensor or ignorant customers who don't tighten the gas cap, however we have had 3-4 of them (in WV alone) that have gone through major transmission repair with under 2,000 miles on the odometer. Average turnaround time on these tranny Nissan's are 2-3 weeks.
Unfortunately Nissan warranty does not provide a "loaner" or courtesy car or aren't obligated to...
But if your tranny runs smooth, it should be a minor repair! Welcome!
