Mileage

[c90]

What would you say would be the minimum mileage per day to keep the 12v Battery charged.

 

[PeteB]

Zero!  

Seriously, it doesn't matter how far you drive, it's time in READY Mode that matters, and the 12V Battery is charged from the big Battery.

In some bulletins Toyota put out during the lockdowns they recommended an hour a week, but I found 20-30 minutes on the drive every 10 days or so kept my car alive just fine.

[Bernard Foy]

17 minutes ago, c90 said:

What would you say would be the minimum mileage per day to keep the 12v battery charged.

 

Is it a modern hybrid you are asking about or the 2000 Corolla ??

[PeteB]

4 minutes ago, Bernard Foy said:

Is it a modern hybrid you are asking about or the 2000 Corolla ??

Oops sorry, after driving Hybrids for 20 years I'm a bit blinkered - must try harder!

[Catlover]

3 hours ago, c90 said:

What would you say would be the minimum mileage per day to keep the 12v battery charged.

 

How long do you leave the car without driving it ?  If it’s any length of time maybe a slow Battery charger would help, a good one can be kept connected and tops up the Battery as required.

[c90]

9 hours ago, PeteB said:

Zero!  

Seriously, it doesn't matter how far you drive, it's time in READY Mode that matters, and the 12V battery is charged from the big battery.

In some bulletins Toyota put out during the lockdowns they recommended an hour a week, but I found 20-30 minutes on the drive every 10 days or so kept my car alive just fine.

Yes I have read about the ready mode, but don't fully understand it.

[c90]

6 hours ago, Catlover said:

How long do you leave the car without driving it ?  If it’s any length of time maybe a slow battery charger would help, a good one can be kept connected and tops up the battery as required.

 

9 hours ago, Bernard Foy said:

Is it a modern hybrid you are asking about or the 2000 Corolla ??

Waiting for delivery of the new C-HR Excel in decuma grey.

[c90]

I am really after first hand knowledge of mileage required to keep the Battery in a healthy state.

The car will be used every day, but was hoping someone who used it for X amount of miles and had no problems would have replied.

[Catlover]

PeteB said in earlier post it doesn’t matter how many miles you drive, it’s how long the car is in Ready mode ie ready to instantly drive away. If you use the car daily to just run 2 mile down to the shops, then 2 mile back, I would suggest every day you do that you are not putting as much back into the Battery as taking out. Get to winter months, and maybe you don’t go out as much then you will be more at risk of the Battery being so low it won’t start the car.

“We” found this out over the last 12 months with lockdown and then the cold of winter. We were going shopping once per week, my car one week, wife’s car the next week. During the cold it took its toll. The official line from Toyota is, if safe to do so, is leave the car in Ready mode for up to an hour regularly. Ready mode means the large hybrid Battery (under the back seat) will charge the smaller 12v battery. This will slowly drain the hybrid battery but occasionally the computer fires the petrol engine into life which charges the hybrid battery that continues to charge the 12v battery. That process of engine running may only happen 2-4 times per hour.                 
Alternatively, when the 12v goes flat you can connect (safely) a battery pack, about the size of a large mobile phone, using crocodile clips provided, across the 12v battery. Within a minute the car dashboard should light up then you can run the car to charge up the battery in Ready mode. Cost around £40-£50 pound.     
Or, and this is what we did, buy a mains powered CTEK MXS 5 slow battery charger which is suitable for both normal acid battery and AGM battery which the CHR may have. During the winter, use the charger perhaps once per week and this should keep car 12v battery in good condition. You do need a 13amp socket and preferably car near your house ie on your drive/garage. This CTEK costs about £70 but is an investment for years.

Hope this helps.

[PeteB]

I've had 7 Prius Hybrids and 1 RAV4 Hybrid since 2002 and done a third of a million miles in them.

Some of the time I did 80 miles or more a day during the week, more recently now I'm retired anything from 10 to 40 miles a day, with a few days a month where the car isn't used at all.  During these times I've never had a problem with either the basic 12V Battery (which mainly starts the computers and runs a few pumps, door locks alarm, lights etc.) or the High Voltage Battery that helps drive the car.

There was one year when my main Hybrid was only used a couple of days a month for mostly short journeys (5-10 miles) and the odd longer one (200 miles), but this caused no problems with the batteries.  It did, however, cause the brakes to rust more and need early replacement, but that's another story.

The the cars have been parked for one or two weeks at airports occasionally (3 weeks on one occasion) and a couple of times during illness the car has been unused for almost a month.  None of these presented any problems.

What can cause a problem with the 12V Battery is very tiny daily mileages (like less than 3), or longer periods of not being used, like during the lockdowns imposed during the Covid Pandemic.  Some people have had problems with 4-5 week holidays.  As long as the car is driven (or at least in READY Mode) for at least ½ hour every week to 10 days it should be fine

The reason I keep coming back to time rather than miles is the is a major difference in how the 12V battery is looked after in a Hybrid to a convectional petrol or diesel car.   When you switch on your C-HR, after a second or so the work "READY" will light up in green on your instrument panel.  This is known as "READY Mode" and means you can drive the car whether the engine is running or not.  Usually, except on hot days, when you start the car from cold after a few seconds the engine will go through a warm-up procedure for a minute or two whether you drive it or not.  After that the engine will start and stop as necessary even while you are moving.  You'll quickly get used to this.

The main point is that while the READY light is lit the big battery runs everything including charging the 12V battery.  So whether you go for a 10 mile drive or just sit in the car without moving for 15 minutes, the 12V battery will be charged as necessary just the same.

I hope that helps, but please come back if you'd like any further clarification.

[TonyHSD]

3 hours ago, c90 said:

I am really after first hand knowledge of mileage required to keep the battery in a healthy state.

The car will be used every day, but was hoping someone who used it for X amount of miles and had no problems would have replied.

Hi, 

the posts above explain the slight difference between standard cars and hybrids, the mileage really it’s not that important as it is the time spent with car set into Ready mode (ON), if you are planning to use the car every day and use it only for a short trips to shops or school runs less than 15min each time then your 12v Battery may have not enough time to be recharged properly and may lost power prematurely, refuses to unlock and start the car. General rule here is as with all other vehicles, more you drive better it is. 

From a first hand now: my Auris hybrid was previously only used for a short school runs in the morning for around 3 miles round trip (20-30min London traffic) and weekends drive outside town for around 40 miles 1-1.5 hrs drive), sometimes the car was also left without any use for up to 4 weeks., then after 3 years of light use I took over and start driving it 200 miles per day and over 10-12 hrs spent time in, we never had any issues with the batteries. 

My advice is to use your car as normally you do but make sure you always keep the car in ready mode while seating inside waiting for someone for example. Keeping your car in ready mode (car ready to drive) recharges the 12v Battery and once in a while a longer outside town trips are also helpful. If you are planning to leave your car without use for extended period of time best to have external source of power like ctek charger, solar charger or power bank especially in cold winter days. If you are using your car every day for 30 min or more you should have no worries then.  
That’s my story, I hope it helps. 👍

[Cyker]

In ICE cars, the 12v Battery is charged by the engine via the alternator - Usually 10-20 minutes of mid/high-RPM driving or 30-45 mins of town driving/idling will put a good chunk of charge into the 12v Battery.

In hybrids and EVs, the 12v is charged from the traction Battery - Usually 30-60 minutes of just sitting there in Ready/On mode is enough to put a decent charge into the 12v battery.

[c90]

Thanks for all your input, I understand a bit better now the ''ready'' mode, all be it a little alien.

Although I have been driving for the best part of 60+ yrs, bikes, cars and HGV Europe I am looking forward to my C-HR and gadgets, which only half will be used.

My concern with the Battery, which has been reported on here and elsewhere, is the hospital visits that me and my wife have to endure now, so reliability is needed.  The reason to move back to Toyota. 

[PeteB]

31 minutes ago, c90 said:

...My concern with the battery, which has been reported on here and elsewhere, is the hospital visits...

In that case, like some of us on here, it's worth keeping a mini jump-starter in the car, but keep it accessible from the front of the car.  If the 12V Battery does go flat, you may not be able to open the boot, nor any of the passenger doors if the car was deadlocked.  I keep mine in the pocket on the back of the front passenger seat.

The 12V Battery lives under the boot floor in many Hybrids, and on those where that's the case there are jump start terminals in the fuse box under the bonnet.

Here's an example: https://www.amazon.co.uk/20000mAh-Portable-Emergency-Charging-Flashlight/dp/B09C247B3L/ref=sr_1_18_sspa?crid=1ZSWCOXYSXZ2H&dchild=1&keywords=jumpstarter&qid=1631980943&sprefix=jumpstarter%2Cdvd%2C245&sr=8-18-spons&psc=1&smid=A271ACC6DCWSTJ&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzSVQ5VzA4QjBYNFZFJmVuY3J5cHRlZElkPUEwNTk4MDAzMVo4NlJRODkxM1pZSyZlbmNyeXB0ZWRBZElkPUEwNTcxMzEzMklFUFdXTFdPU0k0WiZ3aWRnZXROYW1lPXNwX210ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

 

[Cyker]

Yeah, worth learning where the 'jump' terminals under the bonnet are - A lot of people miss it! Or don't realise it's there and try and do it from the Battery which is a massive PITA to get to in a lot of hybrids!

The +/red terminal is in the (usually) left-side fuse box and is under a red plastic cover/tab with a big + symbol on it.

"Ohhh, I thought it was some sort of medical thing!" - My colleague when I showed him after he was complaining about how ridiculous it was to jumpstart it during lockdown

There's usually a handy unpainted nut or strap near the strut tower or engine mount you can use for the negative.

[PeteB]

In the early days of the Gen 2 Prius (2004-2009) there were lots of amusing tales of owners doing all sorts of contortions to climb over seats and into the boot from the driver's door to remove some trim on the back door that gave access to an internal release handle so they could connect jump leads or a jumpstarter to the 12V Battery.  As well as explaining about the jump terminals under the bonnet, the 'technical term' RTFM was bandied about quite a bit in that era!

[c90]

5 hours ago, Cyker said:

Yeah, worth learning where the 'jump' terminals under the bonnet are - A lot of people miss it! Or don't realise it's there and try and do it from the battery which is a massive PITA to get to in a lot of hybrids!

The +/red terminal is in the (usually) left-side fuse box and is under a red plastic cover/tab with a big + symbol on it.

"Ohhh, I thought it was some sort of medical thing!" - My colleague when I showed him after he was complaining about how ridiculous it was to jumpstart it during lockdown

There's usually a handy unpainted nut or strap near the strut tower or engine mount you can use for the negative.

Wow, that's an eye opener, Battery in boot and jump leads under bonnet.

[c90]

5 hours ago, PeteB said:

In that case, like some of us on here, it's worth keeping a mini jump-starter in the car, but keep it accessible from the front of the car.  If the 12V battery does go flat, you may not be able to open the boot, nor any of the passenger doors if the car was deadlocked.  I keep mine in the pocket on the back of the front passenger seat.

The 12V battery lives under the boot floor in many Hybrids, and on those where that's the case there are jump start terminals in the fuse box under the bonnet.

Here's an example: https://www.amazon.co.uk/20000mAh-Portable-Emergency-Charging-Flashlight/dp/B09C247B3L/ref=sr_1_18_sspa?crid=1ZSWCOXYSXZ2H&dchild=1&keywords=jumpstarter&qid=1631980943&sprefix=jumpstarter%2Cdvd%2C245&sr=8-18-spons&psc=1&smid=A271ACC6DCWSTJ&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEzSVQ5VzA4QjBYNFZFJmVuY3J5cHRlZElkPUEwNTk4MDAzMVo4NlJRODkxM1pZSyZlbmNyeXB0ZWRBZElkPUEwNTcxMzEzMklFUFdXTFdPU0k0WiZ3aWRnZXROYW1lPXNwX210ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

 

Think I'll send for one of them thanks.

[Cyker]

It's a nice little quality of life detail I'm glad they thought of due to the difficulty of getting to the 12V (Esp. as it's in a place that is quite hard to get to if the 12V is dead!)

[DavidinDerbyshire]

20 hours ago, Cyker said:

In ICE cars, the 12v battery is charged by the engine via the alternator - Usually 10-20 minutes of mid/high-RPM driving or 30-45 mins of town driving/idling will put a good chunk of charge into the 12v battery.

In hybrids and EVs, the 12v is charged from the traction battery - Usually 30-60 minutes of just sitting there in Ready/On mode is enough to put a decent charge into the 12v battery.

I didn't know this but since I regularly wait for about 20 - 30 mins whilst my wife is shopping and whilst I wait I have it in Ready mode so as to listen to the radio without interruption. The engine sometimes fires up, but not always, so I'm glad to know that  I am unknowingly doing the right thing. On a different note, though, why do they bother having the accessory setting which so annoyingly turns off after 15 - 20 minutes? If we must have it at least give us an over-ride. 

[PeteB]

1 minute ago, DavidinDerbyshire said:

...why do they bother having the accessory setting which so annoyingly turns off after 15 - 20 minutes? If we must have it at least give us an over-ride. 

TBH I've had enough scares that if I use accessory mode it's only for a couple of minutes at most.

A couple of company Vauxhall Cavaliers I had in the 1990s would allow the radio/cassette to be turned on without accessory mode, just by hitting the radio's on/off button.  It would turn off after one hour.