12v battery maintenance, issues, etc.

[Roy124]

John and Robert, my Corolla was ordered in Jan 2020 and I took delivery 6 weeks later.  There were clearly no supply issues or extended parking at the docks as it was made in Derby.

I got the standard OEM Battery. I went flat during the Covid lockdown and twice after that before it was changed. 

The new, larger capacity might have been the only replacement available but I wasn't complaining. 

[Dala]

20 hours ago, CPN said:

This was on first connection this morning after no use for 36 hours... (very cold night, about 4 degrees when I connected - door shut, everything else off)

This was on one push into acc mode...

0.6V-0.7V loss in 36 hours (I estimate 12.5V-12.6V after turning off the car).

This would explain why my security alarm is set to 10.5V - warning - low Battery voltage.

Is 10.5V enough to start the hybrid? Probably yes.

I prefer not to risk it.

Before unlocking the car, I try to ensure that the car Battery voltage does not drop below 12.0V.

[Roy124]

1 hour ago, Dala said:

0.6V-0.7V loss in 36 hours (I estimate 12.5V-12.6V after turning off the car).

This would explain why my security alarm is set to 10.5V - warning - low battery voltage.

You could hit 10.5v in 3 days or less!

[Dala]

22 minutes ago, Roy124 said:

You could hit 10.5v in 3 days or less!

not for me
I reacted to the reduced voltage of 0.6V at Colin
mine was a note for the 10.5v setting on my car alarm
for me, after the car has been standing for a week, the voltage is about 11.9V before unlocking

[Dala]

I would like this car Battery for a hybrid

[RickyC]

19 hours ago, Dala said:

I would like this car battery for a hybrid

Euro -10000 ?

[anchorman]

I said I’d show my remote charging arrangement.  Just a Hive plug which these days shows the wattage draw.  The highest I’ve seen it is 45W and it eventually drops to 1W.   

[StuN]

Our Yaris is 2 years old & has had this exact same issue 4 times. Only now has the dealer agreed to change the Battery. Unlike the OP, it’s used at least 3 times a week & according to the AA mechanic, he sees this problem on the Yaris more than any other vehicle. 
we’ve had enough & are giving the car back. Up until this model we loved the Yaris but we’ll never go with Toyota again. The dealer even tried to suggest they were changing the Battery as a gesture of goodwill until we pointed out that it was still under warranty. 

[TruBlu]

On 1/21/2022 at 6:55 PM, Joby1 said:

Hello

I’ve have a 2020 new model yaris hybrid. In the last 10 days I’ve had to get roadside assistance twice as the 12v battery was dead. First time the car had been stationary for 3 days, the second time 2 days. Dealership today checked if there was a electrical fault (no) but said it needed a full charge up, which they did. Issue is - apparently flat 12v battery is a hybrid issue (due to of engine running from hybrid battery mainly it doesn’t fully charge the 12v.) Apparently there have been cases of people going on holiday for 2 weeks, coming back to a dead battery. I’m concerned as over the next few months due to work I will be leaving my car a few times for a week or two at the airport.

Seems a serious design fault of Toyota when they have a strong reputation for reliability!  
Has anyone else experienced this? Does anyone have a solution? Am thinking I may well be better to sell the car and start afresh. 
Thank you for any advice. 

Same thing keeps happening to my 2021 Yaris Dynamic. 6 jump starts in a year and a half. This is after 3 days of not being used. I know the 12V Battery is not used to crank the engine but is is used to power up other components. As soon as I press the start button I get a dash message saying 'Low Brake Pressure - take to Toyota dealer'. This is impossible if the car won't start. Also the brake pedal vibrates and there is a grating sound. So I jump start the car with a power pack and all ready to go. This is all too common  - not good Toyota - fix it!!!!!.

[FROSTYBALLS]

4 hours ago, TruBlu said:

This is all too common  - not good Toyota - fix it!!!!!.

As we have no connection with Toyota, Toyota won't see this comment.

[anchorman]

3 hours ago, TruBlu said:

Same thing keeps happening to my 2021 Yaris Dynamic. 6 jump starts in a year and a half. This is after 3 days of not being used. I know the 12V battery is not used to crank the engine but is is used to power up other components. As soon as I press the start button I get a dash message saying 'Low Brake Pressure - take to Toyota dealer'. This is impossible if the car won't start. Also the brake pedal vibrates and there is a grating sound. So I jump start the car with a power pack and all ready to go. This is all too common  - not good Toyota - fix it!!!!!.

What did you do before the three days standing?

[anchorman]

I had the back seat out today and while it was out I took a photo of the Battery area.  Might help anyone who wants to add a CTEK connector although personally I wouldn’t bother and do it at the front.  

[RobertR]

Any change to have parn number of that Battery? It's AGM?

[Malomaka]

15 hours ago, anchorman said:

I had the back seat out today and while it was out I took a photo of the battery area.  Might help anyone who wants to add a CTEK connector although personally I wouldn’t bother and do it at the front.  

How easy it it to remove the rear seat, do you have any details?

I have the CTEK comfort indicator ready to fit, but not sure how the seat comes out.

[toyotafan2]

Never had a problem with our lightly used Yaris hybrid. But I did have an Auris hybrid which I bought at one year old and the Battery failed immediately. The dealer replaced it under warranty.

Sounds like you need a new Battery.

[Ken Machin]

It seems that the 12v Battery is not fit for purpose. Twice in the space of a few weeks my car has failed to start although it sits in my garage and is not exposed to extreme cold. I have had to call on Toyota Assist to get me going.

I now discover that this is not just my problem but quite widespread. I understand that by putting the car in ready mode and leaving it for 60 minutes regularly will cure the problem, even if the petrol engine is not running. The 12 v Battery will be charged. I am able to do this in a locked garage, (with appropriate ventilation), but cannot turn off my lights since there is no off position on the new model, unlike my previous Yaris. This I guess will reduce the effectiveness of the charge.

Another way to keep the Battery charged is to use a trickle charger. I have had conflicting advise about this. Both AA men tell me that I can charge the battery using the position connection under the bonnet with the negative attached appropiately to another part of the engine, whereas my Toyota garage says that this is not the case and the battery can only be charged when directly connected. This is difficult due to the position of the battery under the rear seat. Does anyone have a definative answer to this question?

 

 

[flash22]

There are many threads on the subject, some light reading here.............

 

[Cyker]

The simplest solution is basically "Use the car more"

[Roy124]

Use a charger. 

Get a connection hard wired to the Battery.  Save heartbreak. 

[FROSTYBALLS]

Moved to the Yaris forum

[Hibird]

14 hours ago, Ken Machin said:

Toyota garage says that this is not the case and the battery can only be charged when directly connected.

I can't speak for Toyota but I would have no concerns at all using the fuse box location. This has been discussed many times and I have never seen a convincing reason not to use it.

Sorry you have a Battery concern but with a bit of reading here things will get better.

[Hibird]

14 hours ago, Cyker said:

The simplest solution is basically "Use the car more"

Probably not the best advice for someone who does NOT want to use the car more but one that works. Ready mode or trickle makes more sense  and of course making sure the problem also becomes an issue for Toyota.

[davidif]

2 hours ago, Hibird said:

Probably not the best advice for someone who does NOT want to use the car more but one that works. Ready mode or trickle makes more sense  and of course making sure the problem also becomes an issue for Toyota.

I've, personally, never seen the sense in having a relatively new car (a depreciating asset) to only do few miles. surely would make more sense to have a 5/7 year old car?

[Hibird]

Just now, davidif said:

I've, personally, never seen the sense in having a relatively new car (a depreciating asset) to only do few miles. surely would make more sense to have a 5/7 year old car?

The OP choice of vehicle is just that and I don't feel there is any need to critic that choice.

[Roy124]

A second hand car is an unknown quantity.  Only after you have driven it for some time can you take proper possession of it. 

A car owned from new is a known quantity with a dealer support in that first or whatever warranty period.