Side Air Bag Sensor
WARNING: This page is about a different car, the 2002 Lexus ES 300. However, it is still accessible from the selected car via links, so may be relevant.
The side air bag sensor is mounted in right and left center pillar. It consists of an air bag sensor, safing sensor and diagnosis circuit. It receives signals from the side air bag sensor and determines whether side air bag module must be deployed or not.