Driver-Side Air Bag Module
WARNING: This page is about a different car, the 2002 Toyota Highlander. However, it is still accessible from the selected car via links, so may be relevant.
The driver-side air bag module is mounted on front face of steering wheel. It contains a squib, igniter charge and gas generant and inflates the air bag when instructed by air bag sensor assembly. Driver-side air bag module is also known as steering wheel pad.