you most likely have a loose or unattached ground wire to some major component.
yes if one of the wires was getting an earth from the alternator cover or rubbing off the engine the battery light is really an alternator light warning you that the alternator is not charging the battery
Your alternator is defective and not recharging the battery. Have the alternator checked.
When it is no longer able to keep the system charged. Starting with 2001 model, when the car is started, if you see either the battery warning or the battery along with the brakes warnings on, or intermittently flashing on, you need to have your alternator checked. Otherwise, its fine.
The alternator switches off
check the alternator. Use a digital multimeter and with engine running you should have 13-14 volts at the battery. If less than 12.5 Alternator is not charging Also check the amperage the alternator is putting out.
Sounds to be alternator. Take somewhere to have the charging system tested.
Could be the alternator is not charing correctly.
It normally means the alternator is not putting out enough voltage to keep the battery charged and is defective. Can be a loose alternator belt also.
It's alternator time.
Not all the time. The alternator warning circuit wiring to the instrument panel could be grounded
That is the charging system warning light. If it stays on or flickers it means the alternator is not outputting enough voltage to keep the battery charged. With a digital volt meter you should read from 13.5 to 15.5 volts at the battery with the engine running. If not the alternator or the voltage regulator is defective. The voltage regulator is more than likely built into the alternator.
The charging warning light should automatically reset if the battery is disconnected. Check the battery cables and ensure they are properly connected. Also check the alternator connections. If the light is still on there may be a problem with the new alternator.