Battery keeps dying

I leave mine on and they turn off when I turn the car off and open the drivers door. Your's doesn't?

Is the car driven frequently (everyday)? If not, it could be the SKS draining it. Toyota knows this is an issue and provides an OFF button on the lower dash underneath the steering wheel.

 

If you leave by any other door but the drivers, they stay on.
If you open the drivers door before you hit power, they stay on.
The dealer can change the delay to zero seconds, if that would help.
https://www.toyota.com/t3Portal/document/om-s/OM47614U/pdf/OM47614U.pdf
Page 487

 

This should not be enough to drain a healthy battery. I would suggest with a 2009 it's time to change out the 12 VDC battery. Even a healthy battery takes a hit on life span every-time it's drained to the point of needing a jump. Average life is 4-5 years.

 

get a new oem from a dealer. shop around for price.

 

My 12V battery is acting up as well. I have SKS. Sometimes it's barely enough to get the car started and other times it's just fine. I also get random messages about a problem with parking motor (I read that is also a symptom of weak 12V battery). It is doing okay and has not left us stranded yet, but it's definitely not super healthy. I have Torque Pro and that shows 14V - 14.2V while the car is on (normal) and sometimes when I shut the car off I get (GASP!) 10V. However even with 10V displaying in the Torque the car starts and drives just fine.

I am definitetly planning to replace the 12V battery what with New England winter (maybe) coming. I decided on Optima Yellow Top. It is supposed to be a deep cycle battery, which should be better for this type of application. They are pricey, but less expensive than Toyota. I found one for $166 delivered from Jaggs, but they are out of stock until end of December. I placed an order and it should be here in the beginning of the new year.

Am I making a mistake? is the Toyota branded battery the way to go here? If so why?

P.S. I do not know how old my battery is. There is a good chance it's original because I have not seen any records of replacement from the PO who was the only owner. I should get in there and try to find a date code on it, shouldn't I...

 

The 'advantage' of the Toyota Truestart battery is a 84 month (prorated) warranty.

Other than that, it is just another S46B24R battery.

 

Is the Toyota brand battery AGM (Absorbed Glass Matt)? I am pretty sure Optima is, which makes it more desirable. And Optima is advertised as "Deep Cycle", which is also a bit more desirable seeing how Prii tend to drain the 12V with various (small) loads when parked. SKS is of particular concern. I guess if my '07 still has an original battery (albeit on its last leg) I have nothing to complain about. But I am not 100% certain it's original. I am pretty sure it's a Toyota battery. My wife is out with the car right now (I am relegated to our beloved, but old '93 Volvo 940 wagon) and I can't check the date code.

Since most of the replacement 12V batteries for the Prius are really expensive I am going to assume that they are AGM or some sort of gel technology batteries rather than acid sloshing against lead plates kind.

 

Yes, all real Prius batteries are AGM, as (up to Gen 4) the battery is in the passenger compartment with humans, so you want to minimize the amount of battery acid to fly out. They also have weird JIS posts, rather than the more normal SAE posts.

 

Thanks for the answer. I figured as much. I have heard really good things about Optima and I found one for $166 on Jeggs website. The only problem is it ships at the end of December (and probably arrives next year). Everywhere else I saw it it's in the $250 range. Seems like a big difference and I am a bit suspicious... I really like the idea of rolls of lead/acid rather than flat sheets. Seems you can get a lot more surface area that way and increase the capacity of the battery while keeping the dimensions about the same. Also, at $166 it seems like a great deal.

 

$210 with 12 pages of instructions and free shipping

Optima DS46B24R Optima battery direct fit replacement for Prius 2004 to 2015 , Prius V & Plug-in Prius with Instructions

 

VF,

Try going to the autozone website. Enter your car info and do a search for battery. They offer the (Prius) Optima for $185. Your location shows western Mass, so I plugged in zipcode 01060 and it's showing the store at 373 Northampton Rd, Amherst has one in stock available for purchase. I wouldn't wait long, as one episode of "stuck on the side of the road" or "came out of the store and my car is dead" quickly makes a new battery look cheap in hindsight. Especially if the wife is the one stuck.......