One problem related to alternator/generator/regulator has been reported for the 2001 Nissan Altima. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2001 Nissan Altima based on all problems reported for the 2001 Altima.
Vehicle lost speed from 65 mph to 20 mph , and all the gauges on the dashboard shut down, but the engine was still running. Vehicle then went to 0 after about 20 secs. All gauges went dead. Battery light brake light and airbag light come on. Intermittently prior to this other electrical accessories would begin to malfunction heat/air blowers, wipers, lights dimming, etc. Alternator checks good, battery replaced. Runs for a couple days then does it again. Malfuction is not limited to high speed to low. Has happened at varying speeds.