If the battery, drive belt and wiring are okay then I would suspect the alternator is faulty. Your local auto parts store can test the charging system for you at no cost.
Alternator is defective or battery has a dead cell.
Bad alternator or corroded or loose cables.
at the age of 13 and up
Headlights should not be left on while the vehicle is not in use. If you are not driving, you will just drain your battery while having your headlights on.
If a Kawasaki 650 Prairie backfires and bogs down while driving, this may be due to old battery. It is best to change the battery and clean the filters, too.
fuel leaking out drain hose while driving Honda z50
Probably have a 'parasitic load'. This is something causing an abnormal battery drain while the car is off.
Depends on if it drained while you were driving or ran down while it was parked overnight. If the battery runs down while you're driving the vehicle then more than likely the alternator is defective. If the battery drains while the vehicle is parked then the problem is either a dead cell in the battery or a light is on somewhere on the vehicle. Could be a under hood light, trunk, glovebox, dome, or even the brake lights. It can also be a relay that is stuck.
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Your battery is weak, or your your alternator is not charging battery.
You will need to replace your Asus Transformerpad T100 battery if it continues to drain the same amount as if it was in use. Batteries should drain less, not the same, while in sleep mode.
The Legacy subwoofer will really drain your battery. It's not a good idea to run it while you're not running the engine.