Either the battery is not fine and has a dead cell, or something is on pulling power from the battery. Any light on or stuck relay will drain the battery overnight.
Bad battery or a parasitic drain
Yes. If the alternator is dead and you drive the vehicle, all the power is coming from the battery and it will eventually drain completely. Also, if a diode is shorted inside the alternator, that can drain a battery.
A stuck relay in the car can drain the battery. A dead cell in the battery itself will drain the battery overnight. If this is the case the battery must be replaced as there is no way to fix it. To find out disconnect the negative battery cable for around 8 hours. If the battery goes dead it has a dead cell. If not then something is draining the battery. Anyplace that sells batteries can test the battery for you.
Anything that is on and uses electricity. You may also have a dead cell in the battery which will drain the battery.
Dead cell in the battery or something is on pulling power from the battery. If it is a dead cell the battery must be replaced.
a dead battery
Dead cell in the battery, or parasitic drain from a light that is on or a relay that is stuck.
No, a bad ground will not drain the battery. A dead cell in the battery will most certainly drain it. If it has a dead cell it must be replaced. Also any light that is on will drain it. Lastly a stuck relay will run it down.
Alternator is defective or battery has a dead cell.
Example sentence - The dead battery in the truck had to be replaced.
replace it