HELP! My 2007 Prius is dead....(12 v battery....?)

That will work.

And you probably did leave a light on a door ajar. Unfortunately since its been discharged so perfectly and completely (lightbulb) its probably damaged the battery meaning it has begun sulphating. I would not trust that battery again. Do all you can do to have a healthy 12 volt battery. Horrible things seem to happen when a Prius is jump started.

More posted thread on this site is a dead 12 volt battery. Those posters have one thing in common:

They do not set the car alarm every time they park it especially for the night and especially in the garage. That would alert you to a light on or a door ajar.

 

6 years is not too much, if you don't drain it. optima is supposed to be more tolerant of deep discharge, so get a volt meter and keep an eye on it.

 

we all have our strengths and weaknesses. my strength is kibitzing on prius chat. my weakness is kibitzing on prius chat. i let someone else build my house and deliver my kids.

 

You can try re-charging it and see how it goes but if you notice your mileage start to tank that's a sign the Inverter is struggling to keep it charged as it has become sulphated. They do not make battery's like they used to.

I am a maintenance charger. I put my car on a 12 volt charger about once a month. I note how long it takes to charge. I bought my 07 brand new. After I got 6.5 years out of my OE battery, may have gone much longer but I noticed its charging behavior was changing rapidly and I do not want to be stuck anywhere, I bought a new Optima yellowtop same one you have I suspect. I can say the OEM battery showed much better metrics than the Optima has over the last 2 years. The OEM charged faster and stayed charged better than the Optima. The Optima is a very good battery but the OEM was really good based on what I have seen. Charging behavior will tell you everything you need to know about the quality of your battery. So I guess my point is an OEM battery may take a full depletion much better than a Yellowtop.

If it was me I would go buy a brand new Toyota battery and throw it in and be good for another 6 years no worries. If you must roll the dice you can check the battery's charge and capacity by turning on the lights at night before you start the start. Notice if the lights dim at all upon re-boot. If you see any dim at all beware.

Do anything you can do to avoid a Prius jump start. If I had a dead 12 volt battery I would not jump it. I would either charge it like you did in 2 amp mode If I could or flat bed it home. In a jump start scenario you are not current limited. An AAA tow truck shows up and delivers
500 amps of jump power to a Prius 12 volt buss that essentially has a dead short across it. A very heavy duty surge. if your really lucky it will pop the 100 amp hard wired in fuse in the fuse box (nightmare) if unlucky it takes out the Inverter. $$$$$$.

Lots and lots of those story's here on this site.

 

If product warranty is any indication of expected service life, I'd say six years on a lead acid car battery is pretty much it. If you need reliability, it's time for a new battery.

 

1. Do the headlights work now? If they do not work then you are wasting time continuing to try to charge the battery. You need to figure out what is wrong with the 12V battery.
2. You need to do whatever is required to open the hatch so that you can inspect the battery cabling. You may simply have a loose connection. Check the tightness of both battery cables at the battery itself as well as the negative cable where it bolts to the body.
3. When charging a dead battery, do not waste time with a tiny charger especially since you have the alternative of using a larger charger with a 6A setting. Use the latter. The Optima website suggests using a 10A charging rate is fine.
4. You do not need to worry about the float mode. That is useful only if you are going to leave a charger on a fully-charged battery indefinitely.
5. Since the Optima battery is five years old, and considering your FL location, it is certainly possible that the battery may be dead and cannot be restored.
6. I agree that the GS Yuasa battery sold by Toyota dealers is as good or better than the Optima battery. Certainly the dealer battery warranty is now superior, with a seven year term. The True Start labeling is applied to those batteries which have that warranty coverage.

 

Have you tried opening the hatch with the charger connected? The charger might support the voltage enough for that to happen.

Do you own a voltmeter?

 

Your dealer is trying to rip you off. Don't get the stock Toyota 12v, and definitely don't pay $226 for it.

Get one of these Optima YellowTops - https://goo.gl/ZVf9Ax

They're a drop-in upgrade from the stock battery that's supposed to be much more able to survive deep discharges and cold weather. The 12v in my 2007 died about 7-8 months after I bought the car used, I replaced with one of these myself and have had no issues since.

Also, it's a bit awkward to do, but there's an emergency release latch available for opening the rear when the car has no power. Here's a guide with photos - How to Open Your Toyota Prius Trunk (a.k.a Boot) When Your Battery is Dead | AxleAddict

Honestly though the behavior you're describing is kinda odd. Normally even with a dead 12v, you should be able to still jumpstart the car and then leave it on for a few hours to let the inverter recharge the 12v. You've got a charger running at 6amp and you're still not able to jump the car?

If I remember right that setting may actually be too high and may cause damage to your battery.

Here's a YouTube video that shows the Gen 2 Prius' jumpstart terminal inside the fuse box under the hood... You don't actually need to physically access the battery in the back of the car to jump start. Is this where you're hooking up your charger?

 

do any door locks work?

 

if you jump it, do not start the other car, and be very careful about polarity. an expensive mistake for sure, but not easily made.
if you are gonna try and salvage it, you need a digital volt meter to take measurements. and a proper charger.
if not, just take it out, walk it to the dealer and bring back a good one. make sure it's charged before installing. should be close to 13v.