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Yaris Hybrid 12 volt auxiliary battery


Kingsway
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Not only you can’t start it, you can’t push it since you can’t select neutral. If you are unable to get ready to show then the car requires a recovery truck with the ability to lift the car onto the back.


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14 hours ago, Kingsway said:

Nope - the car can do nothing without the 12v supply.  However, I wonder if the 12v battery might recover a little once you take away the load....  It doesn't have to supply a huge current, like a conventional car battery, so you might just get lucky?

OK, I get that.  Thanks.

Unless the 12v is there, the starting circuit wouldn't be there.  The start key would do nothing.  Obvious really.

I suppose if you had an external 12v supply, you could connect it to the car.  ie not charge the Battery first, but just enable the start circuit to boot up.  The traction Battery would then do the charging once started.

Mick.

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Exactly so and as long as your HV Battery was at a nominal state of charge. It's also why there is now a plethora of high capacity (but compact sized) rechargeable Lithium-Ion Battery packs available in the marketplace; some of which are even capable of turning over a conventional starter motor, never mind getting a hybrid going... Untidy jump leads are a thing of the past these days...

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My NHW11 Prius suffered a flat aux Battery one winter a few years back, basically because I'd left it parked outside for a few weeks as I hadn't needed to use it.  The AA man turned up in the snow and plugged in a booster to the Battery in the boot and away it went.  Never had a problem with it afterwards.    

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I wonder if you had a 12v Battery connected to an OBD lead, you could plug it in to allow the car to start.

Maybe instead, a lead that plugs into the cigar lighter, though I don't think that would work as the socket wouldn't be live.

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One of these to maintain a trickle charge through the OBD2 socket. Mixed reviews but could be useful for keeping that 12v aux. Battery on hybrids up to scratch,  if left for long intervals.

https://www.amazon.co.uk/gp/product/B00AC1LLQY/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

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16 hours ago, mrpj said:

One of these to maintain a trickle charge through the OBD2 socket. Mixed reviews but could be useful for keeping that 12v aux. battery on hybrids up to scratch,  if left for long intervals.

https://www.amazon.co.uk/gp/product/B00AC1LLQY/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

I can thoroughly recommend these as I have one myself and it seems to work extremely well even in low daylight conditions...

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  • 2 months later...

LATER:  Four months on, my 12v Battery is definitely giving up the ghost. I've had intermittant problems with the warning lights for Brake, ABS and traction control staying on, or coming only shortly after start-up.  It is happening a lot more now, and the 'cure' seems to be to give the Battery a good over-night charge with an AGM charger.  (My Battery tester seems to show it has only 50% state of health when fully charged)

Has anyone actually had a new aux battery from Toyota?  Is it true they only charge £100, fitted??  The cheapest I've seen it elsewhere is £169.00   I'm sort of tempted to just get a £50 conventional, flooded battery  size 54h  - with a 5 year warranty....

Someone suggested that the aux battery should be covered by the car warranty - but surely such a battery is a 'consumable'?? (It's nearly 4 years old)

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A handy chart showing open-circuit  voltages and state of charge for AGM batteries...

agm-battery.png

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1 hour ago, Kingsway said:

Someone suggested that the aux battery should be covered by the car warranty - but surely such a battery is a 'consumable'?? (It's nearly 4 years old)

Devon Aygo, a moderator on the club and who works for a Toyota dealer, said that the Battery, if failing, should be covered under the new car warranty.

Under Toyota's fixed price repair scheme, a new Battery for a petrol Yaris is £100 - see https://www.toyota.co.uk/owners/service-mot-maintenance/repairs.json

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  • 2 years later...

Ref: Trickle charge OBD2 socket, Yaris hybrid, your Amazon link is no longer working, please let me know the details. Regards Mick

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  • 1 month later...

Hi changed 2 Prius auxiliary batteries last week cheapest was from Toyota main dealer by about 50 pounds

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  • 11 months later...

Has anyone tried replacing 12v AGM auxiliary Battery with a regular 12v flooded one? if yes what has been the long term verict? any long terms concerns? Today I asked the parts guy at the local toyota dealer and he confirmed that a flooded Battery would just work just the same as AGM for the car. Am seeking to capture this from any previous experiences here , please? Greatly apprecated.

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A “regular 12v flooded” Battery will probably work just as well as an AGM Battery, and the Flooded type will be cheaper then an AGM as you probably aware. But why is there an AGM Battery fitted in the first place?             
A Regular 12v flooded battery has acid sloshing around in it. If that battery was split open the acid is the unrestrained, and in the case of an accident could splash about. In an AGM battery, the acid cannot do that as it’s is Absorbed in a Glass Mat. 
So where is the 12v battery in you car? If it is under the bonnet then in case of an accident and the battery gets split the consequences of the acid endangering someone is low. However, if the battery is within the cab area, as in under the rear seat (or in the boot area as with some Toyota hybrid cars) if the 12v battery was the flooded type and an accident occurred where the battery split, this could result in passengers getting acid burns which would not be good. Hence, for those type of vehicles am AGM type battery is fitted for safety reasons.

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49 minutes ago, Catlover said:

A “regular 12v flooded” battery will probably work just as well as an AGM battery, and the Flooded type will be cheaper then an AGM as you probably aware. But why is there an AGM battery fitted in the first place?             
A Regular 12v flooded battery has acid sloshing around in it. If that battery was split open the acid is the unrestrained, and in the case of an accident could splash about. In an AGM battery, the acid cannot do that as it’s is Absorbed in a Glass Mat. 
So where is the 12v battery in you car? If it is under the bonnet then in case of an accident and the battery gets split the consequences of the acid endangering someone is low. However, if the battery is within the cab area, as in under the rear seat (or in the boot area as with some Toyota hybrid cars) if the 12v battery was the flooded type and an accident occurred where the battery split, this could result in passengers getting acid burns which would not be good. Hence, for those type of vehicles am AGM type battery is fitted for safety reasons.

Thanks Joe for your insightful reply, v v much appreciated. From what I can make it of it, it's exclusively to safety toyota goes for AGM. I asked on doubt whether a flooded Battery would just die too early for being used as an auxiliary. Since AGM are marketed to be slower in losing charge and lasting longer. my current one lasted 9 yrs for example, it's still usable, it did leave my wife stranded but when I got him charged it put it back, its been working for the past week or so, im carrying a spare flooded Battery atm until I narrow down if its due for replacement or not to avoid being left stranded.

 

thanks again

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If you got 9 years out of any Battery you can’t grumble if it stopped working today…… having said that I hope it keeps going. 😄

 there are other benefits to AGM, you mentioned longevity. All depends on how you treat them, you must have done something right over the years. Obviously not letting them get flat is one benefit. With jump starts being not much more the size of a smart phone it sounds sensible to have one for say £60. I also have the. CTEX 5, which I use 3 or 4 times per car! Keep it up on charge as we don’t use our cars a great deal, pre covid 7k, and 5k, maybe we will get back to that soon.

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On 2/20/2022 at 3:44 PM, Catlover said:

If you got 9 years out of any battery you can’t grumble if it stopped working today…… having said that I hope it keeps going. 😄

 there are other benefits to AGM, you mentioned longevity. All depends on how you treat them, you must have done something right over the years. Obviously not letting them get flat is one benefit. With jump starts being not much more the size of a smart phone it sounds sensible to have one for say £60. I also have the. CTEX 5, which I use 3 or 4 times per car! Keep it up on charge as we don’t use our cars a great deal, pre covid 7k, and 5k, maybe we will get back to that soon.

I never complained about current Battery, 9 yrs is amazing. Although my first car had a flooded-type Battery that lasted 15 years and didn't fully die on me, just gives me one start after every drive, hence unreliable if you stop and start often. I think I'll be going down the path of a flooded Battery for my yaris hybrid and hope for the best that it doesnt drain too quickly for auxiliary usage. someone else was right to post here that toyota do give a discount on the AGM they sell, instead of Eur190 they sell it for Eur150 with 3 year warranty. 

Will keep you guys posted here. thanks again for your input

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