Temperamental Prius

Hi all,

I have a 2008 Prius with 55k miles. Recently (within past month) had 50k check at Toyota Service station.

Here is the scenario…

I drive to work just fine. When need to run an errand 2 hours later, the car will not start. I put key in an press power button (with brake depressed, all the normal lights on the dash light up, but engine doesn’t turn on. There are some funny things like gas light on, but full tank. I press the power button again, and the car beeps continuously (beep, beep, beep as opposed to beeee…eeeeeep) until I remove the key. I tried turning it on multiple times, with similar results. Fast forward 6 hours, I go to try it again and it turns on like nothing had happened previously.

I called Toyota, and they said the auxiliary 12V battery was likely dead (despite having just driven to work), and it recharged itself after sitting for a while. They said that it should be replaced… I am suspicious that it might be an electronic issue or something else - does anyone have any ideas?

The battery is 5 yr old. U can have Toyota tech look at ur car for 2 hrs @$105/hr or replace battery.

A weak 12V battery can cause various odd problems. Since it’s original I’d get it replaced, then see if other problems are present. Prepare for a shock - the replacement’s small but expensive, and takes a bit of labor to swap out.

O’Reilly seems to have a 12V Prius battery. Still kind of pricey.

Install it yourself and save a few bucks. Don’t rush it. Allow yourself an hour.

Notice the part number?!


I would avoid an Optima battery, if some parts store wanted to sell you one for your Prius.

But that’s just my opinion.

Great, thanks for your help!