Sudden 12V battery failure

bredekamp · 03-22-2008, 01:45 PM

Went to my prius about an hour ago and tried to unlock her...nothing.

bum bum buuum!!

Tried using the key...nothing. Phone Toyota road-side assistance:"It's easter weekend we cannot help you".Okeey.

Tried the key again. You have to twist REALLY hard. I then opened the bonnet and jumped the car with a small 12V battery I had. Once I had the trunk open I shut everything down again. After removing the 12V battery I tested it with a multimeter. It read 11.96V. I opened the battery (it's not sealed) and checked the water level. One cell was dry and 3 others were low. I topped them up and its' happily charging now.

This failure was very sudden. I'm pretty sure I didn't leave anything open or on. I have noticed sluggish boot-ups for the past two weeks, but I thought I was imagining it. The battery is about 18-24 months old now.

MUST I use the Toyota GS battery or is their a cheaper alternative?

qbee42 · 03-22-2008, 01:47 PM

There are alternatives, but it takes a little handy work for mounting. I recall that the terminals are different too, so you need an adapter. A quick search will fill you in on the details.

Tom

bredekamp · 03-22-2008, 01:52 PM

What's the typical lifespan of these 12V batteries?

Flying White Dutchman · 03-22-2008, 01:54 PM

looks like 2 year are normal for failure!

bredekamp · 03-22-2008, 01:57 PM

Quote:

Originally Posted by Flying White Dutchman

looks like 2 year are normal for failure!

I'm glad it happened with the car at home and not at work or in a mall parking lot. I'm gonna start keeping a small "jumper" battery in the car.

People, keep a small 12V battery in your car for jumping.

Flying White Dutchman · 03-22-2008, 02:16 PM

Quote:

Originally Posted by bredekamp

I'm glad it happened with the car at home and not at work or in a mall parking lot. I'm gonna start keeping a small "jumper" battery in the car.

People, keep a small 12V battery in your car for jumping.

mine failed after 2 years to
i now have a solar charger to keep it charged when standing still

firepa63 · 03-22-2008, 02:48 PM

I'm still running 4 years on mine with no problems. It's possible that you depleted the battery at some time and now it will not take a full charge.

bredekamp · 03-22-2008, 03:47 PM

Some of the cells were dry. How could this happen? I had a look and there are a number of locally made equivalents for the 12V battery. Not identical, but they should work.

okiebutnotfrommuskogee · 03-22-2008, 03:48 PM

Quote:

Originally Posted by bredekamp

I'm glad it happened with the car at home and not at work or in a mall parking lot. I'm gonna start keeping a small "jumper" battery in the car.

People, keep a small 12V battery in your car for jumping.

I agree with you. Here is my back-up arrangement. "EMERGENCY BATTERY PICTURES"

Patrick Wong · 03-22-2008, 04:22 PM

Quote:

Originally Posted by bredekamp

...After removing the 12V battery I tested it with a multimeter. It read 11.96V. I opened the battery (it's not sealed) and checked the water level. One cell was dry and 3 others were low. I topped them up and its' happily charging now...MUST I use the Toyota GS battery or is their a cheaper alternative?

Could you please post photos of the top & side of your GS battery? It is supposed to be absorbent glass mat which means that it should not have free liquid in any of the six cells.

When you opened the battery to look at the cells, did the lead plates look like a normal battery or did you see anything strange (like the fuzzy white mats that are between the plates in an AGM battery)?

I posted photos of the GS battery from my 2004 equipped with SE/SS, which is AGM since no sloshing sound is made when the battery was shaken. #1 shows the 2004 battery at the bottom of the photo, compared to the battery from my 2001. #2 shows the side view of the 2004 battery.

If you can find a vented AGM battery that is rated 31-32AH or better, that fits the available space with the correct terminal polarity, and has the correct size terminals, then you are good to go. A regular lead acid battery is not recommended for safety reasons - if your Prius is hit in the right-rear fender, you probably don't want liquid acid everywhere.

03-22-2008, 01:52 PM	#3
bredekamp Senior Member Join Date: Feb 2007 Location: Somerset West, South Africa Posts: 569 My Car: 2006 Prius Model: Package: #6 Touring Thanks: 4 Thanked 11 Times in 7 Posts Friends: 0	Re: Sudden 12V battery failure What's the typical lifespan of these 12V batteries?

03-22-2008, 01:54 PM	#4
Flying White Dutchman Senior Member Join Date: Dec 2007 Posts: 3,754 My Car: 2005 Prius Model: Package: Thanks: 153 Thanked 234 Times in 193 Posts Friends: 15	Re: Sudden 12V battery failure looks like 2 year are normal for failure!

03-22-2008, 02:48 PM	#7
firepa63 Former Prius Owner Join Date: Jul 2005 Location: SE Pennsylvania Posts: 1,750 My Car: Other Hybrid Model: N/A Package: N/A Thanks: 9 Thanked 186 Times in 154 Posts Friends: 0	Re: Sudden 12V battery failure I'm still running 4 years on mine with no problems. It's possible that you depleted the battery at some time and now it will not take a full charge.

03-22-2008, 03:47 PM	#8
bredekamp Senior Member Join Date: Feb 2007 Location: Somerset West, South Africa Posts: 569 My Car: 2006 Prius Model: Package: #6 Touring Thanks: 4 Thanked 11 Times in 7 Posts Friends: 0	Re: Sudden 12V battery failure Some of the cells were dry. How could this happen? I had a look and there are a number of locally made equivalents for the 12V battery. Not identical, but they should work.

03-22-2008, 01:45 PM	#1
bredekamp Senior Member Join Date: Feb 2007 Location: Somerset West, South Africa Posts: 569 My Car: 2006 Prius Model: Package: #6 Touring Thanks: 4 Thanked 11 Times in 7 Posts Friends: 0	Sudden 12V battery failure Went to my prius about an hour ago and tried to unlock her...nothing. bum bum buuum!! Tried using the key...nothing. Phone Toyota road-side assistance:"It's easter weekend we cannot help you".Okeey. Tried the key again. You have to twist REALLY hard. I then opened the bonnet and jumped the car with a small 12V battery I had. Once I had the trunk open I shut everything down again. After removing the 12V battery I tested it with a multimeter. It read 11.96V. I opened the battery (it's not sealed) and checked the water level. One cell was dry and 3 others were low. I topped them up and its' happily charging now. This failure was very sudden. I'm pretty sure I didn't leave anything open or on. I have noticed sluggish boot-ups for the past two weeks, but I thought I was imagining it. The battery is about 18-24 months old now. MUST I use the Toyota GS battery or is their a cheaper alternative? __________________ My Prius.co.za Hybrid vehicle information for South Africa

03-22-2008, 01:47 PM	#2
qbee42 My other car is a boat Join Date: Mar 2006 Location: Northern Michigan Posts: 17,746 My Car: 2006 Prius Model: N/A Package: #7 Thanks: 1,354 Thanked 2,797 Times in 1,880 Posts Friends: 19	Re: Sudden 12V battery failure There are alternatives, but it takes a little handy work for mounting. I recall that the terminals are different too, so you need an adapter. A quick search will fill you in on the details. Tom