So my car's battery died, I blame me for not driving it for a week and the weather dropping to the mid 30's at night , i went to crank it and there wasn't a Volt of charge, usually, when the battery is low on power it will sputter out and give a half-assed crank , what i do is turn the charger to 12 V "CRANK" and she fires right up , I quickly disconnect the charger and the cables because I'm scared of frying anything. Today It was dead dead, as in 0 volts so I Tried the 12v CRANK setting and all I got was a click, no crank, immediately disconnected the system. Should charge it at 6v or 12 v , the CRANK setting just adds extra amperage.

 

It's a 12V battery and system, charge it at 12V. Sounds like you need a new battery, or there's some electrical gremlin draining away the charge.

 

You should charge it with the "12V" setting (which is really 14.4 or should be).

Unfortunately, when a lead acid cell is deeply discharged, lead phosphate forms, blocks surface reactivity at that site and diminishes the capacity of the battery.

 

I charged it for half an hour, the car started right up, sadly I think Toruki is right, my dad gifted the battery to me three years ago, it was new but the battery has never been used until 4 months ago . The two times it had died i left the AC/ Radio on and it drained it within a day .

 

The cold really stresses batteries. And showing 0V is a bad sign . Face palm, I wrote phosphate where I should have said sulfate.

 

If in the future you need to charge this battery or another, you will want to slow charge the battery at 12V with low amperage. If the battery is failing, its best to replace it.