After finding a helpful Instructable on the topic, he had full access to the sensor’s signals, allowing him to easily wire it up to an Arduino.

Electromechanical PIR-Sensor Interface IC Controls Any AC Load Oct. 8, 2008 The LS6506R is a pyroelectric infrared (PIR) sensor interface IC that is designed to drive a latching relay.

The module houses a PIR motion sensor, ultrasonic sensor and dual-stack radio providing both Bluetooth® and 2.4GHz wireless capability.