WARNING: This page is about a different car, the 2008 Suzuki Swift +, 2008 Pontiac Wave, and 2008 Chevrolet Aveo. However, it is still accessible from the selected car via links, so may be relevant.
The output shaft speed (OSS) sensor (1) is located on the upper position of the transaxle and detects the vehicle speed from the rotation number of the differential gear.