Likely the charging system has failed. You will need to check voltage at the battery with a Digital Multi Meter (DMM typical <$15 at home improvement store). A fully charged battery will read 12.5VDC or better while engine off. It may start with a slightly lower voltage, but won't run for long. With a good charging system and engine running, you should get 13.5 to 14.75VDC at the battery. Less than 13.5 volts means charging system has likely failed.
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Likely the charging system has failed. You will need to check voltage at the battery with a Digital Multi Meter (DMM typical <$15 at home improvement store).
A fully charged battery will read 12.5VDC or better while engine off. It may start with a slightly lower voltage, but won't run for long.
With a good charging system and engine running, you should get 13.5 to 14.75VDC at the battery. Less than 13.5 volts means charging system has likely failed.