There are a couple of ways to charge a battery in a 2005 DeVille. You can use jumper cables with the use of another battery. You can also use a portable battery charger.
It would depend on the condition of the battery and if the battery charger has a jump start mode.
I have a 2000 Deville DTS. The battery is located below the back seat. Just pull up the seat (not back), and you will find the battery.
use a 10mm wrench and remove the battery from the trunk compartment, and replace it with the new battery
its time to get a new car. dont stay in the past
The battery is located under the rear seat.
It is located under the rear seat. The seat is easily removed by lifting sharply on the lower front lip of the seat.
Dead cell in battery or the alternator is defective. That is assuming all words are connected and not corroded.
Voltage regulator or loose wire.
Maybe your new battery is dead or needs a charge before using.
under the back seat
you would buy a new one ,charge it, or call someone who knows more
its under the back seat....