Car starting

yes, the 12v operates some things while the car is off. it also has a capacitor for emergency braking, should it run too low.

 

that would be non sks, unless something is wrong. check the bottom of the dash under the steering wheel for an sks on/off button.

 

yep, that is tpms. so you want a non sks battery. double check the measurements before buying, the sks is larger and won't fit.

 

You can also check the 12v battery from the car's computer screen. Very important not to use the car overnight (10 hours) before you do the test:

Weird stuff happening? MPGs dropping? Test The Battery | PriusChat

 

Info for all...
SKS model....S46B24R and CCA=325
NON SKS model....S34B20R....CCA=272

If I remember right, it has the 20H rating on top near the model number

 

Which is a dead give away that the battery is dead. Or maybe not well connected. Given that it jumped and ran OK, but went weak after lots of short runs that didn't let it get well charged, I'd say it's the 12V battery. But it only takes a few seconds to find out.

 

Go to a Toyota dealer. On sale the battery costs $175.

 

You may want to look at the battery that's installed in your car to verify which model it is. It would stink to go hunting for a small battery and then find out a previous owner changed over to the larger model, like some owners do.

 

Looks a lot like this one. I bought this one about a year ago to use as a back-up in case any of our Prii had a battery failure. It tested at 375CCA about 5 days ago using my electronic tester. If it comes down to it and you can't find a replacement within your time requirements....I'd sell it for what I have in it. It's been installed twice and has about 3 days of use on it

 

I also think I have a large battery mount in the shop if you're interested in switching over to the larger model, which seems to be more readily available.

It wouldn't be too hard to just completely remove the small mount system, pack a towel into the bottom of the cubby and drop a large model battery on top of it. Then hook up your cables. Stuff some rags on the three sides of the battery away from the trunk vent to keep battery from bouncing around. Order a large mount kit.

 

The bigger battery will work very well and would be a better option. You just need to swap the battery bracket which cost about $20-25 from the dealer or grab the one TMR-JWAP has, if he can locate it.

When looking for an after market replacement make sure you get an AGM battery, not just a flooded lead/Acid which are considerably cheaper. The experience seems to be that to find an after market that is equal to the Toyota is harder to find due to the limited amount of after markets that meet that criteria. And sometimes after markets are not cheaper.