12v battery maintenance, issues, etc.

[1.33]

Does the Battery drain affect all grades or only the higher spec models equipped with smart entry etc?

I only use the car at the weekend and the issues with the Battery drain on the Mk4 have put me off from ordering one. My previous Toyotas have always started 1st time even when parked for up to 3 weeks.

[Roy124]

17 minutes ago, 1.33 said:

Does the battery drain affect all grades or only the higher spec models equipped with smart entry etc?

 

My Design, no smart entry has suffered flat batteries but only once over 8 days.

[Roy124]

On 8/4/2022 at 11:48 AM, isnsiie said:

 I just bought my 2016 Yaris in April this year from the dealer. I use it 2-3 short trips a week. It cannot start up itself last week, need a jump starter to start.

I sent it to Toyota service centre and they said the 12V battery is dead due to my low usage.

I know Battery natural life has been mention.  The other factor is historic Battery usage.  In the previous 6 years that Battery may have been thrashed and be weakened.  Either way a battery change is the way forward. 

[Joby1]

My car is smart entry. All my passed Yaris’ since 2006 have been smart entry too (never had a problem starting even when left for 4 weeks whilst in NZ) but this is the first hybrid model I’ve had. The AA chaps who have been out to me (3) have each said they been to a number of Yaris hybrids with same problem - I assume they won’t all be smart entry but don’t know for sure. 
Mon Toyota’s own chat site there are lots and lots about this same issue. Main advice Toyota seem to be saying is drive the car regularly each week or do the routine of leaving it in start mode for 60mins each week or install a solar trickle charger which their dealers will fit - I think for a couple of hundred pounds. 
 

I really think this is a fundamental design fault of the hybrid engine model(Yaris at least) and therefore Toyota should hold their hands up and acknowledge that - after all one of the key reasons people but Toyota is their reputation for reliability! And so for existing owners for a solar trickle charger free or develop a fix (applied via a recall) which sets up for the v12 Battery to be topped up/trickle in effect from the hybrid Battery. If not, for new buyers their sales pitch should include a mandatory statement explaining a threshold weekly usage is required. For these changes to happen though will need a campaign and public/customer pressure - I don’t know how to go about even starting that? 

 

[Roy124]

Joby, it is a hybrid issue not make or model specific.  Different manufacturers have tackled the problem in different ways. 

I think Kia have the option to switch the hybrid Battery to energise the 12v.  This means the hybrid only feeds the 12v when you do that switch. 

I get the impression that Toyota only recognised the size of the issue with lock down.  Prior to that occurrence was probably much less. 

For new cars the problem will go away on 12 years. 

[Roy124]

My garage are hard wiring a CTEK lead to my Battery.  I will be able to simply plug in my charger. 

It will also allow me to connect a jumper Battery and I might add a solar panel too. Need to play with the CTEK plugs but not difficult. 

[Cyker]

Annoyingly this problem has existed for ages; I remember it being an issue with the 1st gen Auris when that came out too. That said, I do think it's more down to the car not being used enough. Maybe they should have put a higher current DC-DC converter to charge it faster?

 

 

[isnsiie]

On 8/6/2022 at 8:39 PM, Cyker said:

Annoyingly this problem has existed for ages; I remember it being an issue with the 1st gen Auris when that came out too. That said, I do think it's more down to the car not being used enough. Maybe they should have put a higher current DC-DC converter to charge it faster?

 

 

the 12v Battery need to be charged with a very low current. 

[Roy124]

7 minutes ago, isnsiie said:

the 12v battery need to be charged with a very low current. 

Indeed, faster isn't the problem, as Cyker says, it is the car not being used.  

They should be looking for an engineering solution not an after market band aid. A physical switch to allow the hybrid Battery to provide the necessary 12v feed to the computer would do it. 

I know Kia has some procedure and an instruction not to jump start. 

[Llynyfan]

With my new Mazda Yaris on order, I wondered if this was still a problem. It is in more ways than one. Ive just been out to go shopping and my CHR (hybrid) is on the drive waiting for a garage to come to fix. Battery problem again, not experienced since lockdown and I've neglected it by not using it since last Thursday! 

I've read some threads, here and on other forums, we're not alone on this one 😭😭

[Roy124]

2 hours ago, isnsiie said:

 

 

1 hour ago, Llynyfan said:

With my new Mazda Yaris on order, I wondered if this was still a problem. It is in more ways than one. Ive just been out to go shopping and my CHR (hybrid) is on the drive waiting for a garage to come to fix. Battery problem again, not experienced since lockdown and I've neglected it by not using it since last Thursday! 

I've read some threads, here and on other forums, we're not alone on this one 😭😭

Sue, yes it's still a problem.  Thursday to Monday is a very short period for failure.  Usual questions - has it happened before - yes, lock down, which leaves the other question. 

How much had you driven in the days before Thursday? 

In my 8 day case I think it was its first failure and it had been driven for 3 hours before being garaged. 

 

[Cyker]

4 hours ago, isnsiie said:

the 12v battery need to be charged with a very low current. 

Nah, lead acid batteries can take quite a lot of current - A lot more than NiMH and Li+ can - It's one of the reasons they're still used in cars despite NiMH and Li+ batteries being much lighter and having better energy density.

There is a limit, where if you go past it hydrogen will literally boil out of the Battery, but this is a known quantity and charging can be limit or cut off before that becomes a problem. Additionally, most car batteries are sealed to stop being a problem, allowing the hydrogen to re-combine safely into the acid, with over-pressure valves to stop extended hydrogen build-up getting too dangerous (read: explosive) pressures.

The charge limit is lower in AGM and Gel batteries than it is in flooded batteries, but it's still pretty high.

[MikeSh]

4 hours ago, Llynyfan said:

Battery problem again, not experienced since lockdown

Was it replaced after that event?

Deep discharge can cause permanent damage/aging, so once it's happened you are possibly looking at a much shorter remaining life. I expect to replace these every 6 years or so even if not abused, so 3 years for a wounded one would not surprise me.

[Cyker]

The biggest weakness of lead acid batteries is they don't like being deep-discharged; It's not as bad with deep-cycle lead acid batteries (Flooded, gel or AGM), but starter batteries (flooded, gel or AGM) really don't like being discharged past 50%, and if it's done repeatedly the Battery usually requires replacement...

 

[Llynyfan]

Not replaced after last events, there were two, even when the AA guy tested the Battery and it showed it was like the parrot in the Python sketch, by the time I had driven it to Toyota they returned it saying, nothing wrong. 

Prior to Thursday and including Thursday, unusually three round trips of at least 50 miles of mixed roads, only AC and the radio on, no lights, wipers, wintery stuff.

Takes the edge off Toyotas reliability claim with so many instances and them suggesting to customers they buy a solar or other trickle charger is absurd, time it was standard equipment if they cant sort out this issue and keep it as such until they have sorted.

My mother in laws Polo was MOTd on Friday, flew it as usual. So what? 2004, 23000 genuine miles, basic servicing and last year it broke the 1,000 mile mark in a year for ages. Should add and dont want to curse it, cant remember having a new Battery on it. Progress I suppose.

[Dala]

50% for an AGM Battery is 12.06V
usually is indicated 40% - 20% = 11.9V - 11.58V - does not recommend repeatedly falling within these values
below these values is permanent damage
these values are valid for 25°C

[Roy124]

Sue, I suspect too late to get it changed on warranty, but for others, I monitored Battery voltage over a number of days and showed the garage the steady and quite rapid drop over 4-5 days.  They eventually changed the Battery without arguing. 

Obviously you need to have a period of 4-5 days without using the car.  I think it was TonyHSD that advised  not opening the driver's door as that activates and deactivates the fuel pump. 

 

[Dala]

the killer of car batteries is smart charging!
12.8V-13.2V is not a Battery charging voltage!
the capacity is lower in winter - e.g. -20°C is only 60% of the Battery capacity
the solution for the 35Ah Battery is to return the charge to a value higher than 13.6V

[Llynyfan]

Thanks @Roy124 Im parting with it in September for a Mazda Yaris. Well thats the plan, from one hybrid to another, so Ill note all the advice 👍

[flash22]

18 minutes ago, Roy124 said:

Sue, I suspect too late to get it changed on warranty, but for others, I monitored battery voltage over a number of days and showed the garage the steady and quite rapid drop over 4-5 days.  They eventually changed the battery without arguing. 

Obviously you need to have a period of 4-5 days without using the car.  I think it was TonyHSD that advised  not opening the driver's door as that activates and deactivates the fuel pump. 

 

That would be the vacuum pump for the brake booster

2 hours ago, Cyker said:

Nah, lead acid batteries can take quite a lot of current - A lot more than NiMH and Li+ can - It's one of the reasons they're still used in cars despite NiMH and Li+ batteries being much lighter and having better energy density.

There is a limit, where if you go past it hydrogen will literally boil out of the battery, but this is a known quantity and charging can be limit or cut off before that becomes a problem. Additionally, most car batteries are sealed to stop being a problem, allowing the hydrogen to re-combine safely into the acid, with over-pressure valves to stop extended hydrogen build-up getting too dangerous (read: explosive) pressures.

The charge limit is lower in AGM and Gel batteries than it is in flooded batteries, but it's still pretty high.

AGM is a Low <4A and slow, as it's a deep cycle type too much current can fry the gel and break the mats down, the Mk4 uses an LN calcium-metal Battery yet another type

[Llynyfan]

I know my radio in the greenhouse has 2 aa. I bow to your knowledge which I just cant get my head around 😃

[Derek.w]

I wired my Yaris up for both CTEK 3.8 amp charger or solar charging.

Normal charge voltage 14.4 summer winter mode 5 degrees or lower 14.7

Float charge ither mode 13.6 volts

Solar output upto 22 volts Battery pulls this down have not fitted a solar controller.

[Dala]

[MikeSh]

48 minutes ago, Llynyfan said:

I know my radio in the greenhouse has 2 aa. I bow to your knowledge which I just cant get my head around 😃

All batteries are - ultimately - consumables. When they're done, they're done, like oil and filters.

In the overall costs of running a car for a few years a new 12V Battery is a blip.

It letting you down because it wasn't changed out when it should have been (because the AA or some other 'experts' said it was OK) is another level of annoying. Personal choice whether you want to pay now or gamble for a bit more life (Battery life that is 🙂 )

[Mikw]

6 hours ago, Roy124 said:

 

Sue, yes it's still a problem.  Thursday to Monday is a very short period for failure.  Usual questions - has it happened before - yes, lock down, which leaves the other question. 

How much had you driven in the days before Thursday? 

In my 8 day case I think it was its first failure and it had been driven for 3 hours before being garaged. 

 

That would be my question too.

How was it driven in the days before Thursday? If a couple of short journies then i can see that depleting it enough for it not to have enough charge after a few days of non use.

However, if it had been in "ready" mode for an hour then it shouldn't have had a problem being left for a few days.

 

Edit : just seen the reply, so it seems it's because it's run down a couple of times before it's probably damaged