2007 prius won't start

Yep, she's dead; new 12v aux battery is in order. Jump it from the bonnet dedicated fuse box jump point with a 10amp fast charger.

 

Yes, sounds like the 12v (this is not the hybrid battery) has finally given up. Not surprising in the cold. As already stated, you can jump it or try to recharge it some under the hood in the fuse box on the driver side but make sure you know what you are doing. You may not get a second chance to hook it up correctly. Positive to positive and negative to negative. Doing this wrong even for a split second could cost in the 4 figures. It's easy to do it right but just saying.

 

My question is that how many batteries does prius 07 has? I wondered that 12v battery is the part of hybrid battery pack. Pls elaborate so as to clarify the same. Thanks.

 

Sajjad, the Prius has two batteries. One is the HV (high voltage) hybrid traction battery. This is the expensive one but is made to last the life of the car and fortunately rarely fails. The other is the 12 volt auxiliary battery. This one often needs replacing in 4-5 years. There are several options for the replacement but they are still limited. This is not exactly the same size as most other car batteries. This one will typically cost under $200 in the states.

 

Ok thanks Steve for your kind reply..

 

Be very careful if you jump the Prius make 100% sure you connect + to + and - to - as if you get it wrong even for a split second you can do a lot of damage to the Prius.

Do not run the engine on the truck while you are jumping the Prius this to can do damage. The Prius does not need much current to get it into ready mode "no starter motor" it just needs to start the computers.

Leaving the Prius in ready mode will charge the battery no need to drive it. It will charge even when the engine is not running as long as it is in ready mode.

John (Britprius)

 

Suitable replacement batteries are. OEM (Toyota 200$), Optima yellow top, Exide Edge FP-AGM51JIS.

If your car has SKS all these batteries are direct fit. If your car does not have SKS system the Optima and the Exide will need the larger battery tray for the SKS version of the Prius available from Toyota.

 

You can jump it, charge it, or let the Prius charge it but you may find you have the same problem after it sits a little while. It has been warning you for quite a while now so the 12v is likely in very bad condition that may prevent it from holding a charge. But it's worth a try. I would not feel comfortable going anywhere and turning it off unless it was at the place to replace the battery. It's a good idea to have whoever you buy from to put a volt meter on the battry before installing. 12.8v is a fully charged battery. 12v is less than 50% state of charge. Many times a battery will lose voltage sitting on a shelf so the fresher the better. No need to start off with a weak battery.

 

Yep sounds like a 12V. You got off easy on this one. I think it is about $300 at the dealer. They can confirm. Just a heads up they may have to order it from the Parts Distribution Center which is a 1 day delay in most places.

 

They last about 5 years so you did better than average.

 

First get "Prius User-Guide" look on line for: john1701a.com/prius/prius-userguide.htm ...it will give you more useful info than anything Toyota has!! Had a very similar issue with my 2005. It has "smart entry key" so I thought it was the battery in the FOB, and the dealer said it probably was but by putting the FOB into "key slot", in dash, it would get me home....{this by-passes 12v btry and uses other to start car}
I stopped at "Batteries Plus" and they tested the 12v battery, discovered it was dead, then replaced with
Optima Batteries 8171-767 Yellow Grp S46b24r 450cca by Optima

$200.00 installed! - great deal, great people, back on the road with no problems. 110,000 miles on the original 12v battery - hope this one last that long.....oh did I tell you, I live in Minnesota with 4-5 months of winter with sub-zero temps! Good luck!!
Berkley

 

Brit, u used a terminology "SKS" in your above thread. Pls can u tell what's that mean?

 

Smart Key System

The non-SKS equipped Priuses used a smaller battery.

 

JOHN(Britprius) - Thanks for the hint. Between this chat and the "Weird stuff happening?" - which I highly recommend to find the onboard 12v battery diagnostic, my son and I were able to jump our dead Prius (mobile battery pack from Costco) and bring our baby home for 8 hours of "Ready" charging.
BTW - a hint from one who has accomplished it - the small terminal in the fuze box under the bonnet/hood of the Prius is useless for most American jumper cables. It's about 3/8" diameter bolt that is set into a fuze holder which does not allow any access with traditional heavy jumper cables. After finding this out, I went to the 12v battery in the truck (is there a british term?) and used the battery studs. Since there is nothing to 'turn over' it was simply a matter of looking up to the MFD and see that it had turned on. Once we did this, we went through the diagnostic on the MFD and found that the battery had 11v. We're now on our way over to Battery +Plus to get the Excite.
I highly recommend doing the simple battery diagnostic before the winter season to see the condition of the battery.
John in Del Mar

 

Thank you for your reply. I do know about the MFD voltage check procedure but being a retired electrical engineer prefer to use a meter for this purpose as after checking a number of Prius cars I find the reading on the MFD to under read by as much as .5 volts.

It does however give once used a reading that will give an indication of the state of charge of the 12 volt battery. The terminal under the hood (bonnet in UK) is a little small but the plate at the side of this can also be used.

Boot is the UK term for trunk. If you wish to thank someone click on the word like at the bottom of there post.thanks again.

John (Britprius)

 

I believe that is incorrect. Putting the FOB into the key slot does not bypass the 12-volt battery; it bypasses the Smart Key function so that an FOB with a failed FOB battery can be used to start and drive the car — so long as the 12-volt battery is functional. If the 12-volt battery is dead, it doesn't matter where you put the FOB.

 

Regarding a dead (or dying) Prius 12v battery: I was fascinated to hear from "Britprius" that leaving the Prius in "Ready" mode for 8 hours or so will recharge the 12v through the HV. This worked like a charm, and in a pinch (ie after hours and son far from home). He left it in a garage (secure), with the door open a crack since the gas engine will start occasionally. I couldn't find this type of post anywhere else.....

 

Mine will not start either.
It has a recently replaced 12v battery.
inside lights and headlights work okay
also tried inserting the key into the slot
dash lights that normally show when starting do not come on
can use the fob to lock and unlock the doors
cannot lock or unlock the doors with hand
must use the unlock function of the fob to unlock and lock