Based on my experience, I'm not sure the 12v battery is all that important. My 2008 Prius (bought used in 2015 with 150K on it) was showing signs of needing a new 12v battery in 2019.. This guide will teach you how to replace the 12V battery in a 2nd-generation Prius. The 12V battery is an essential component of the hybrid car that allows the accessory mode and the hybrid battery system to start up.
If you suspect that your 12-volt battery is malfunctioning, follow these steps to confirm or deny, that the 12-volt battery is the problem with your Prius: Power up your Prius: This will give you access to the car's settings, which are going to come in very handy. Go to the 'Display' Setting: Go to the settings menu, and then click display.. Prius 12 volt replacement battery. For all Prii the 12 volt auxiliary starting battery is located in the rear of the vehicle, towards the rear of passenger compartment or trunk. Because normal lead-acid batteries create small amounts of hydrogen gas during charge and discharge, the Prii use a modified version of the lead acid battery (called.