12v battery maintenance, issues, etc.

Do you drive short rides? For example, twice a week only 5 to 10 minutes?

In April 2020, Toyota gave the following advice on Battery maintenance due to cars being left for long periods without use: https://mag.toyota.co.uk/coronavirus-toyota-hybrid-car-maintenance/

It isn't just a hybrid or Toyota problem, as petrol cars and cars from other manufacturers may be affected as well. For example our 2020 i20 comes up with a Battery drainage warning a few minutes after the engine is turned off and the multimedia unit is still on.

What you haven't said is whether your normal usage is short journeys, etc. These together with electrical systems like lighting being on a lot, etc, don't help provide the Battery with a full charge.

Yes, you can sell the car, but may have a similar experience with the replacement - who knows ?

Thanks everyone for your advice. 
daily I usually do 2 x 10 mile drives. 
 

I am a new hybrid owner but had my previous petrol yaris 14 years, 135,000miles. No Battery problems. 2019 left it for 5 weeks whilst in NZ, started first time on return. 

Joby, you almost have to unlearn what you new. Hybrids are a step change in specification and understanding. The Battery issue might be said to be a fundamental step change in much the same way that Diesel car drivers had to learn about DPF and then Ad Blue. 

Things will change. 

I can only advise this :

About once a week leave it in ready mode for an hour. It's the short journies that kill the Battery. So, if you've done a couple of short drives then - next day - give it an hour in ready mode, and that should last a week or so.

The key is "ready" mode really. If you wash the car yourself, leave it in ready mode, the engine will only come on a couple of times over an hour. Same if you put the car in the garage, don't switch off when you get out to open the garage door.

It seems to me that short periods in Ready mode deplete the Battery, but longer periods in ready mode keep it topped up.

40 minutes ago, Mikw said:

It seems to me that short periods in Ready mode deplete the battery, but longer periods in ready mode keep it topped up.

...and you should also add that longer periods in ready mode knock hell out of the overall fuel consumption figure per tankful! (because it's standing still - going nowhere)

I don’t think so Colin. I have done the one hour in ready mode and the engine did fire up but not many times and not for long. It’s not like the engine is running all of the time.

If it's in winter and the HVAC is on then it would drop the mpg quite dramatically, but with it off or in summer it is surprisingly frugal still; When I was stuck in yet another M25 closure for 2 hours (THANKS SMART MOTORWAYS) last summer, I think I only lost 1-2 mpg just sitting there in Ready mode with the AC on (albeit in eco mode) listening to music  

34 minutes ago, Catlover said:

I don’t think so Colin. I have done the one hour in ready mode and the engine did fire up but not many times and not for long. It’s not like the engine is running all of the time.

I didn't suggest it was but nevertheless, I am not going to sit there waiting for someone at this time of year without the heater keeping me warm and the windows mist free either. Quite often after immediately filling up (and the tankful average mpg zeroing) I can nurse a 60+mpg for quite some time even in this weather but if I stop and wait in ready mode for 20 mins or so, that overall tankful mpg figure will plummet by 5 mpg at least in very short order! (in this sometimes sub-zero weather we've had recently) It's mostly because the system struggles to get the ICE much above 50°C to get some temperature into the heater.... (and NO, I am not going to sit there and freeze with no heater on! 😉)

Update , I went out to start the Yaris this morning and the dash lit up but the car wouldn't start.

On looking down at my charging socket in the cigarette lighter which has a voltage display , only 7.7 volts was showing so I decided to give the Noco a go.

It was easy to find a suitable earth point close to the fuse box and within seconds the engine fired into life.

We had an appointment to get to and the Noco saved the day..

Yes, as you found out it doesnt take much to fire one up, by the time you connected the portable Battery and get back to the car cockpit then its virtually ready to go. Now you got to get that Battery up to 100% and thats where something like the XTEX 5 comes in. That will slow charge up to 80% relatively quickly but to get it up to 100% could take another 8 hours or more. One feature with the CTEX 5 is that you can unplug during a charge and next morning when you reconnect the unit picks up from where you left off.

Our test will be in March.  Airport valet parking.  I am certain they will have a jump start capability.  Just hope they have hybrid knowledge too 😁

23 hours ago, Catlover said:

I don’t think so Colin. I have done the one hour in ready mode and the engine did fire up but not many times and not for long. It’s not like the engine is running all of the time.

Yep, if you do it without the heater on the engine in the Yaris Mark 4 only comes on two or three times during that hour for a minute or two at most, as long as the traction Battery is well charged.

Is it easier to charge the Battery with Battery charger? The fuse box contains a charging connector.

54 minutes ago, Yaris Hybrid 2021 said:

Is it easier to charge the battery with battery charger? The fuse box contains a charging connector.

It could be easier but not always convenient ie if no off street parking and you have to stay with the car. A charger may take a lot longer then the one hour Ready charging, albeit a charger may do a better job as they are “smart” and can take the charge up to 100% slowly, and can recondition a Battery. A good smart charger, though, costs a few 10’s of pounds, CTEX 5 for example £70.

Didn't DevonAygo say in another thread that you shouldn't use that connector to charge the 12v Battery...?

Why?

16 minutes ago, Yaris Hybrid 2021 said:

Why?

There is no connection from the under bonnet starting terminal to the 12v Battery, when you connect power to the terminals you are sending power to the DC/DC converter just like the cars 12v Battery however on separate circuits that do not join.

12 minutes ago, Devon Aygo said:

There is no connection from the under bonnet starting terminal to the 12v battery, when you connect power to the terminals you are sending power to the DC/DC converter just like the cars 12v battery however on separate circuits that do not join.

So, when I connect a CTEX 5 under the bonnet of the wife’s 2010 Auris hybrid what happens?

1 hour ago, Devon Aygo said:

There is no connection from the under bonnet starting terminal to the 12v battery, when you connect power to the terminals you are sending power to the DC/DC converter just like the cars 12v battery however on separate circuits that do not join.

Interesting. I've charged my Corolla via both the main terminal (one with the M8 stud) and the blade connector with the red cover. Both times I confirmed current flow with an ammeter and the charging took hours to complete. Are you sure the two distribution points are not joined internally?

Next time, I could pop into the boot and check if the potential does indeed raise at the Battery posts when I connect from the fusebox. But there's energy going somewhere, that's for sure.

Here's an excerpt from my owners manual. It's one of the steps that explain how to perform a 'jump start' using the fusebox terminal:

5. Start the engine of the second vehicle. Increase the engine speed slightly and maintain at that level for approximately 5 minutes to recharge the 12-volt Battery of your vehicle.

I'm aware that this is the Yaris forum, so apologies if I'm jumping to false conclusions with my Corolla example.

Ok,  so I plan to buy a ctek MXS 5 at the weekend and the adapter kit for permanent Battery connection , I'm assuming that those of you using this set up would leave the charging cable hiding behind the access panel when not being used ?

My Corolla Battery is under the bonnet.  I routed the extension cable to the right to be nearer my charger.  I leave the extra curled up on the right. 

Any Mk4 Yaris owners out there using a Ctek charger  ?

I'd really like your opinions on the best way to hook up the charger to the 12 volt battery  ?

Thanks..

Tomorrow I will take a photo of the connections you get with the CTEX 5 and post them on here for you.