My 2001 Nissan Sentra suddenly out of no-where will not start anymore. I am trying to diagnose and learn how to solve this problem myself for educational purposes. Here are the details I have diagnosed:
-The car will not turn over (no chug-chug-chug noise). When I turn the key, I hear just a click.
-If I connect my dead batter to working car's battery with jumper cables, my car starts fine
-I unhooked my bad battery, plugged it into a trickle charger overnight and put it back in the car. I checked the voltage reading 24 hours after charging and it reads 12.5-12.6v (which at first I thought meant my battery was okay?). However, when I put the battery back in the car, it still wont start.
-If I boost the car with jumper cables, and check the voltage of the car while its running, I get around 15v with nothing on, and if I turn my headlights, heater, and turn up my stereo loud, it goes down to about 14.8-14.9v.
Questions:
1) Does my voltage test while the car is running verify my alternator is okay? Ive been told to check the batter voltage while the car is running and if its above 14.7v while the car is running ,then my alternator/charging system is functioning properly. Anyone confirm or deny this for me?2) My motomaster car battery charger has a 2A/12A/75A settings. The
75A setting even says "car boost" or something to that effect. When I hook up the car battery charger up to my battery and set it to 75A, the car will NOT start this way (It did a little chug-chug once, but usually just makes the click sound). Is my motomaster car battery charger just not powerfull enough to boost my car? Or is there something else going on here I am not aware of?Is the problem just my battery is dead? I want to make sure Ive done all the tests to verify that it is my battery that needs replacement before I go out and buy one.