I have a 2016 altima with 26k miles..I've replaced battery and have had it checked 2 weeks later and its good,took it to dealer Saturday and tech said nothing wrong just need to drive more (really ?)....got up Sunday went to start and battery dead again...any ideas ??
If your battery is draining after one or two days, then the battery may be no good; get the battery tested. If the battery is in good condition, then there may be a parasitic draw occurring in the electrical system. In this case a parasitic draw test needs to be performed; there should not be more than a 50ma (milliamp) draw on the system with the ignition switch in the "OFF" position. If there is a higher draw, you need to do some testing to find out where the draw is coming from. Remove fuses one at a time until the draw goes away or falls into acceptable range.
With late model cars that use intelligence technology, e.g. key FOB, you should wait at least 30 minutes or more before performing a parasitic draw test. The draw will generally drop below 200ma within 2 minutes after shutdown and may remain that way for up to 30 minutes after the doors are closed. The BCM usually hibernates in 30 minutes and the draw should drop below 20ma at that point (13ma is probably average).
If you do these tests, make sure all accessories inside the car are shut off; this includes any courtesy lights such as the overhead lights. If the hood has an opening security sensor, it must be disabled. All the doors and trunk must be closed; if you need to have the driver's door open, put something against the door button to keep it pressed in order to break the electrical circuit. There should not be more than a 50ma draw on the system with the ignition switch in the "OFF" position. The reason being is the ECU and IPDM are always on in sleep mode which accounts for the very small draw.
