Pry the lower end of the bench back to release clips Lift bench out Lower end ofback of seat is held in by either 2 bolts or clips that are now accessible - release these and you will be able to slide back up toward rear windshield to release
its under the back seat....
under the back seat
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.
Its under the back bench seat on the passenger side.
The back seat should pop out and your battery and some fuse boxes are under your back seat.
Answerthe battery for the 2000 deville is usually behind the back seat*EDIT* To be more clear it is UNDERNEATH the back seat not behind it. Lift the portion that you actually sit on and you will find it.
On a 79/80 Deville there are nuts under the seat that have to be loosened and be careful of the power seat wires and mechanisms under the Seat.
There is one under the hood on the driver side and one located in the trunk on the back of the back seat.
Under the back seat. Pull the bench seat up. You will feel the clamps releasing it. The fuse box is now visible to the left of the center.
Check under the back seat or there may b a panel covering it in the trunk
in the trunk behind the rug on the back of the rear seat drivers side
it is located uper the back seat. which some times shorts out the rear heated seats.