1999 Cadillac STS Replace Battery
The 1999 Cadillac Seville STS's battery is located under the back center seat cushion--an unusual location, considering that most car batteries are located in the engine compartment. Changing the battery in the Cadillac Seville STS takes more work than usual because of its location, but car owners can still handle the replacement by themselves. When the battery is no longer able to start the engine, replace it with a new battery.
 Tools Used
|8mm or 10mm wrench|
 Replace Battery
- Lift up on the bottom of the center rear seat cushion to detach the hooks, then pull up and toward the front of the vehicle to remove the cushion. The battery is located below.
- Pull the two vent hoses out of the vent sockets on the left and right sides of the battery, and lift the battery cover.
- Remove the negative battery cable by loosening the bolt on the cable clamp with a wrency and lifting it off the terminal. The negative cable is often black; the negative battery post has a minus (-) symbol next to it.
- Loosen the positive battery cable clamp bolt with a wrench and lift the cable off the positive battery terminal. Positive battery cables are often red. The positive battery terminal has a plus (+) symbol next to it.
- Remove the battery holder bracket with the wrench. Then lift the battery out of the battery holder. Take care when lifting the battery, as car batteries are heavy.
- Set the replacement battery in the battery holder and reattach the holder bracket. Ensure the negative and positive battery terminals are in the same location as the old battery's were.
- Connect the positive cable to the positive battery terminal by sliding the positive cable clamp over the terminal and tightening the bolt with the wrench.
- Attach the negative battery cable to the negative battery terminal and close the battery cover.
- Push the air vent hoses onto the air sockets on both sides of the battery. You risk sulfuric acid fumes entering the cabin of the vehicle if you do not reattach the vent hoses.
- Buckle the center seat belt to prepare to reinstall the center seat cushion.
- Route the seat belt through the slots on the seat cushion and place the back part of the cushion under the seat back. Push the seat cushion fully under the seat back to ensure it is fully installed.
- Press down firmly on the front of the center seat cushion until you feel the left and right sides of the cushion latch.