SRS Operation: Notes
WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.
The main circuit in the SRS unit senses and analyzes the force of impact and, if necessary, ignites the inflator charges. If 12 volt battery voltage is too low or power is disconnected due to the impact, the voltage regulator and the back-up power circuit will keep voltage at a constant level.