jumping 12 volt drained battery

Open the hood, remove the fuze box cover. Attach the Positive cable to the RED Positive connector.
Place the ground/black cable to the engine block. Press the Start button...

How old is your 12V battery? If it's 5 or more, you should probably replace it.

 

The quick jump connect under the hood is an easier way to access the only 12v battery that is actually in the trunk. Do not disconnect the ground wire. Feel free to hand him the manual, but if you don't know how to jump this car, your advice to the pro may do more harm than good.

Posted via the PriusChat mobile app.

 

And yes, you do need to do more than drive it around for a short while. Unlike other cars, Prius can only fully charge the battery by keeping the car running for 8-20 hours (or trickle charge for a couple days).More importantly, you need to find out why you need a jump start (left the door ajar overnight and or lack of use for the last 6 months?). You need to find out if you need a new battery...how old is it?

Posted via the PriusChat mobile app.

 

At 4 years, the 12V should be okay. But as kenoarto said, you need to find WHY it was/is dead.
Check ALL lights. Do you have anything plugged into the cigarette lighter plugs?
How often do you drive, and for how long?
You should get a volt meter so you can check the battery voltage. If you don't drive much or far,
the hybrid battery can't charged the 12v battery long enough, and it will get weaker and eventually
will be low enough that it's won't engage the computers and be able to trip relay to start car.
A battery tender, or trickle charger could keep the battery topped off. If you get an AGM charger,
no more than 4 amps according to Toyota, then you can fully charge it and then maybe once a week
put it on the battery over night to keep it fully charged.

 

Those instructions for recharging the battery over several hours are different than for jump-starting. You would never disconnect the battery for a jump start.

 

Sure. IF you drive continuously for about 24 hours.
Seriously, just normal driving won't be good enough.

A 4 year old battery that has gone flat probably needs to be replaced.
If you actually have access to a power outlet near the car, NOW would be a good time to get a battery tender.......which would save you the hassle of a service call AND might get you a few more good months out of it before it dies again. Might.

 

Maybe.
After letting it go DEAD, probably not.

 

Anybody disconnect their ground while trickle charging?

 

That appears to be what Toyota is recommending in the above quoted charging instructions. Personally, I think that's preposterous.

 

Never. At least so far, but I've only been taking care of my cars for about 50 years. And I just topped off my wife's battery yesterday since I had all the doors open while doing a project that took several hours.

 

We own a 2008 Gen 2, a 2012 Prius V, and my 2015 Gen 3. Drove the latter from the house to the post office (a couple miles) last night, came out, tried to start and got nothing except a flickering "key not found" warning. Huh. Turned out to be nothing but a 12 volt battery that had suddenly and dramatically died. I carry a little jump starter battery pack, couldn't get good connection from the emergency jump start in the fuse box (possible the wires were too short to find a really good ground). Crawled through the back, opened the hatch, jumped and drove home.

(I bought the little jump starter battery pack because I won't jump start FROM my Prii -- it's nice to have so I can still be a helpful chap -- hadn't really thought about NEEDING a jump!)

The original Yuasa was still in there, my bad, I should have replaced it at about four years. New Optima installed, but, holy cow -- NAPA charged me over $350! Moral of the story -- had I replaced it at four years I'd have saved over $100 by getting it in the mail (it's a Guam thing -- no Wally World here).

There had been NO warning -- no reduced mileage, lights, etc. It just suddenly would not start. The shelf life of any battery is limited.

 

Probably a good idea to do voltage checks with a meter once a month after about 5 years...

 

You have NAPA in Guam? Who'da thunk it?

 

I don't see the point of complaining about the price of ANYTHING when you live on Guam.
Having said that, I don't buy anything from NAPA anymore because of their high prices.
But sometimes there isn't a practical alternative.

 

Three stores!

 

Yup, totally my bad!