Record all of the customers radio station presets.
Turn OFF all the lamps and accessories.
Make sure the ignition switch is in the OFF position.
Grasp the engine control module (ECM) and slide the retainer rearward until the retainer disengages from the 4 clips on the battery cover. Reposition the ECM out of the way.
Release the side snap retainers (1).
Remove the battery box cover (3) from the retaining tabs (2).
Remove the battery box cover (3).
Loosen the battery negative cable terminal bolt.
Remove the battery negative cable from the battery.