DTC P0722: Output Speed Sensor Circuit No Signal: Reference
WARNING: This page is about a different car, the 2004 Suzuki Grand Vitara. However, it is still accessible from the selected car via links, so may be relevant.
Connect oscilloscope between "C51-1-10" (+) and "C51-1-9" (-) of PCM connector connected to PCM and check output speed sensor signal.
Fig 1: Identifying Oscilloscope Waveforms At About 40 km/h (25 mile/h)