99 suzuki vitara v6 turns on all power but wont

The starter uses 10x more elect. power than the head lamps
or 100x more than dash lamps. it means little.
what matters most is jumper cable starts.
does it crank with jumper cables to a running, donor car,(aaa jump)
no bad starter
no, bad starter key line( immobliizer or such) ask how to test.
yes, cranks great, now.
that means the battery was dead,
i charge the battery and it now cranks, due to lights left on or
charge system failure, if battery goes to 13.3 to 15v running good
if on the charge system failed. (causing battery discharge)
if after charging a battery it will not crank car, its a bad battery (jumps ok)