Drained Battery?

12V battery......

 

Well, your 12v battery lasted almost 4 years, pretty much what any car does.

Dead Car Battery | How Long Batteries Last | Auto-Facts.org

 

I purchased my 2008 Prius in April 2008. After less than a year old, the 12V battery seemed to drain very quickly. After several jump starts, I took it back to the dealer. At first they refused to replace the 12V battery. But after some thorough testing, they finally admitted that the 12V battery was defective. That was March 2009. It worked perfectly since then.

Yesterday, I had left the car unattended for 7 days and I found the 12V battery completely drained. I called CAA for a boost and drove the car around for about half an hour to recharge the battery. The CAA driver said that I need to make sure the car is not left idle for a long time during winter.

This afternoon, I went to check on my car in the underground parking. I was able to use the alarm to open the doors. So, I thought everything was fine. But, when I tried to start the car, the car would not start and the dashboard lights just faded within seconds. The 12V battery was dead once again.

This is so aggravating. I want to take it back to the dealer. But, they're already closed and won't be open till Monday morning. I don't want to call CAA again since it'll just be a temporary fix and I don't want to use up one of my CAA emergency calls. I might have a friend help me jump start the car tonight.

Just to give you a quick backgrounder. I bought the car in Los Angeles where I used to live. I now live in Toronto. The only modification done on the car was the DRLs which is a requirement here in Ontario, Canada. When the dealer tested it last year, they eliminated the possibility that the DRLs (installed by a 3rd party) were draining the 12V battery.

What do you think is the problem? I can't believe I've been very unlucky with 2 defective batteries.

 

Did you leave the smartkey turned on for those 7 days? (it can be turned off with a swtch below the steering wheel if you know you're leaving it for a week). I expect it got completely drained and then froze (was it someplace cold enough?), breaking something inside. A drained battery is basically just filled with water. That means a new battery.

It probably takes more than half an hour to charge, and you don't need to drive it to do this.... just ready mode is fine. So get the boost and leave ready for a few hours.... it may recover some if it didn't freeze... it won't recover all the way though. A total drain ages a battery a lot.

 

Would buying this booster pack help in cases of emergency?

Motomaster 500A Booster Pack | Canadian Tire

 

Yes, I didn't turn off the smartkey switch.

The car is parked in the underground parking. It's cold down there. But, above freezing since it's heated. I've left the car idle for more than a week before without turning off the smartkey switch with no problems.

Should I get a booster from Canadian Tire just for peace of mind? Is this the right one for the Prius?

Motomaster 500A Booster Pack | Canadian Tire

 

Tell us the odometer reading on your car, how often you currently drive it (i.e., daily, 2x per week, etc.) and how many miles per week the car is currently driven.

I am wondering if the root cause is that the car is not driven enough to keep the 12V battery charged.

 

I have about 16,000 miles on the car. My daily mileage is about 30 miles. I drive the car pretty regularly. The only times the car is idle is when I go out of town where I leave the car idle in the underground parking for about 5 to 6 days.

 

Sounds like reasonable daily usage. It appears that your second 12V battery is bad and will need to be replaced.

Since you mentioned "underground parking", I assume you live in a condominium or apartment building so you probably can't use a battery charger or battery tender.

As BAllanJ pointed out, if your battery is low enough to need a jump start, 30 minutes of driving is not going to be enough to recharge it. More like 12 hours of continuous READY status is necessary.

 

Patrick, would this portable booster work?

Motomaster 500A Booster Pack | Canadian Tire

 

Seems like a good choice. 14Ah capacity is around 40% of the Prius 12V original equipment battery.

The only concern is whether the positive battery clamp is too big to fit on the dedicated positive jump start terminal in the main relay/fuse box. Since you've had prior experience jumping the car, I assume you know what I am referring to and have figured out how to deal with that small terminal if needed (if not, use a binder paper clip <might have to scrape some of the black paint off to provide electrical conductivity>, an alligator clip, or something similar to attach to that terminal, then attach the jumpstart clamp to the clip.)

The negative clamp can attach to the nut holding the top of the driver's side suspension strut to the body.

 

Patrick and BAllanJ, thanks a lot for your replies. My friend helped me jump start the car tonight. Then, I drove it for 2.5 hours. Hopefully, it'll start tomorrow morning. I'll buy the booster pack at Canadian Tire. Then, on Monday, I'll take the car to the Toyota dealership.

 

I own one of CTC's booster packs, but it's a very large overkill one for other purposes (and for boosting other people).

 

Good news! The car started this morning.

I ended up buying the Bonaire Power Boost 5000 Jumpstarter at Costco. There was a $20 coupon expiring today.

BallanJ, thanks again.

 

Do you always lock the car when parking it? Doing so helps avoid common battery killing conditions.

 

i have a 2008 prius as well i purchased a truck over the weekend and let it sit idle for 3 days. The car appears simply Dead no power to anything. The proper jumpstarting method i have read thus far is from the fuse box but im confused the Dealer when i bought the car showed me the terminals in the rear trunk or are these only for attempting to jumpstart other cars. I have purchased a B/D jumpstarter from wally world. This particular model i have had some previous experience with. so i trust it.

my curiosity is that i normaly drive 150 miles per day. the car has 88k on it. and it just went poof. do i follow the procedure and then go to Toyota for evaluation of the 12 volt or just jump start it and then watch it and decide from there.

sorry for the ramble.
all comments are welcome.

 

Since you drive 150 miles per day, the battery has plenty of charging time. If you can't identify any driver error (such as leaving cabin lights on, a door or the hatch ajar, etc.), then I'd suggest you replace the 12V battery. If you can DIY you'll save a labor charge.

You can jumpstart either from the dedicated positive jumpstart terminal in the main relay/fuse box; or at the battery. Whichever you find easier.

 

You can easily confirm before spending money:
http://priuschat.com/forums/newbie-forum/73400-weird-stuff-happening-mpgs-dropping-test-battery.html