Frequent dead battery??

damn i never heard of this problem before. but im really hoping you just have a bad 12v battery and nothing else.


are there any electrical mods done to the car? i know its still like new, but doesnt hurt to ask.

also if you leave the car in the on position the battery will drain which might be happening. if you leave the car in ready position then it shouldnt matter.

i have never turned off anything like radio or ac when leaving the car. i just turn off the car and thats it.

i and i think everybody else will tell you to just take it in.

 

Check to make sure the car is in Park. Sometimes it will act weird when it's not in Park.

 

At this point you need a new battery and it's probably NOT covered by warranty. If the car sat on the dealer's lot for 6 months the battery may have been damaged by being fully discharged a number of times. The tiny Prius batteries do not survive this type of abuse.

 

Was the dome light on with the front doors open? And maybe "courtesy" lights in the doors? Any lights in the front foot wells that go on? Several hours thus can kill the puny 12 volt. Coupled with: if it's a new car, it's likely been sitting on the lot, or in transit, for some time, not been run enough.

You might check the voltage with a digital multimeter, and try reviving it with a low amperage smart charger.

 

Pretty much what Mendel said. Unless you somehow left some lights on when you walked away, having the doors open and radio on would not have killed your 12v battery.

The battery MAY have been compromised by being on the lot for a while, but I've never seen it happen in real life. Any running the car would have recharged it after you purchased it.

Your best bet before buying another VERY expensive Toyota battery would be to charge the one you've got and make sure absolutely every light is off, doors closed, switches switched, and all that. I suggest a Battery Tender brand smart charger. I believe these are available at Wal-Mart. Get a digital multimeter and check your battery. It should be 12.5v to 12.75v fully charged. If it's below 12v it's suspect, charge it. If it's below 11v it may be hosed, but charge it anyway and start over. Overnight on the charger should do it. I would unhook the terminals from the car and charge it overnight in that condition...but that's just me.

Read up on your owner's manual while you're waiting.

Good luck!

 

check out the battery testing threads, i think you're still under warranty, at least pro rata.

 

once the car is in the ready position the 12v battery should never be in a problem since the hybrid battery is now charging the 12v battery and also supplying power to the car.

the 12v batteries are small because they are only really meant to keep the computer settings and other settings stored and also for keyless entry and stuff. the manua states that when using the car while standing, always put the car in the ready position. when im working on the car i always turn off the dome light just to be safe.

 

Yes.....except for the part about the warranty.
No reason to believe that it would NOT be covered.....IF it can be shown to be bad with a test.

Those who have never heard of this kind of problem haven't been reading all the posts very carefully.
Pretty much ALL hybrids have small 12 V batteries, no matter what model or make.
It is a common problem across the board for those people who are in the habit of having electrical things ON when the car is OFF.......and for those folks who make only a few short trips or leave it sit for more than a week at a time.

If you own a hybrid, a smart tender-type battery charger is almost a required accessory.
You WILL need it eventually.

In this case, and other similar ones, giving the battery a really good charge might solve the problem for a while.....might.

 

Whenever you're going to have the doors open for some time, it's good to shut the dome light right off. And turn off any other lights you can. The battery is puny. Personally, I have the dome light on ours permanently off, just too many bad experiences.

Running the car will recharge the battery to some extent, but it's asking too much if the battery's been seriously discharged. Yeah, do look into a smart charger.

12.43 Volt your reading sounds promising, especially considering that just from driving a bit. If and when you hook it up to a recharger, don't recheck voltage right after. Drive it a day or two first before checking. It'll read falsely high right after charging. If you're at 12.6 volt (or close) you're in good shape.

 

I bought a new Ford once. They needed to jump the battery to test drive it. The battery would not hold a charge and had to be jumped when I got gas. The replacement battery from the dealer was dead in 6 months. I replaced it with a Sears battery and it lasted 5+ years.

 

In hindsight, I was very lucky on my 1986 Accord. An interior light at been left on during a previous test drive, completely draining the battery, so had to be jumped for my test drive. It then lasted 8 or 9 years.

But that was clearly an exception, many other members here have opposing experiences.

 

Almost the exact-same thing happened with my new Prius plug-in. The aux battery would go dead within 10-15 minutes of having it in "acc" mode. I took it back, and after testing the battery, they said it was indeed defective and they replaced it free of charge.

The dealer had kept it in the showroom for a long time, and the salesman said it was a "very common" occurrence for it to have gone dead many times, and boosted, which eventually destroyed the battery. They kept the hybrid charging cable plugged in all the time, and apparently assumed (as I did) that would keep all batteries charged. This is definitely not the case.

Since that time, I have found that leaving it in acc mode, and forgetting about it, will not kill a good battery. Mine will auto shut-off after a number of minutes (maybe 30?) thus preserving the aux battery. If the battery is in poor condition however, it will go dead before the automatic shutoff occurs. My suggestion was that acc mode should auto shut-off based on low battery voltage instead of a timer.

 

There's a VW dealership near us. One time I noticed all the cars on the lot sporting a small solar panel on the dash. Assume the car's had constant-on 12 volt outlet to facilitate this. Last time we walked by didn't see those anymore, maybe not effective? But a good idea I think: lots of cars sitting around dealership.

Our's had been on the lot a long stretch I think. Twelve volt was completely toast when we purchased, so they replaced at the outset.

 

I wouldn't assume that whomever plugged those solar chargers into the lighter sockets knew whether they were always-on or keyed. Most of the newer vehicles I've seen, have switched power to the lighter sockets, with the exception of sockets which are clearly labeled as "always on."

 

Maybe that's why they quit using them, lol. Dang things weren't making any difference.

This trend to keyed 12 volt outlet can't be good for aftermarket accessories that depend on constant 12 volt outlet.

 

I had a difficult time installing a dash-cam in my Prius which required both a constant-on power lead and a keyed acc lead. That's why I switched to a better one which uses only the switched 12V socket, and relies on an internal battery to retain memory settings and to activate recording when the shock-sensor registers an impact while the car is parked.

 

My favorites have been Battery Tender brand.

http://batterytender.com/

I have used them to keep the batteries of the, Z28, mower, and the motorcycles charged during the off season, and the truck simply due to not driving it very often. Quick, easy, and pays for itself for keeping some batteries a year to two or three longer.