2019 CHR battery keeps discharging

[96McKJ91]

Hi all, new to this forum so please be patient. 
I have read some of the discussions relating to the above issue. This has now happened to my car even when I have recently ran the car on ready mode for an hour. 
I have had the AA out twice in the past week and now the car is not starting again today. 
I have tried charging with an electric powered jumpstart cable but it’s been 2 hours and still not starting. What am I doing wrong?

I use the car most of the week normally to work Monday to Friday 10 min - 30 min journey each time and occasionally over the weekend - I have only had the car since February 2023 and have done a round trip of 5 hours out and 5hrs back in march but now back to doing my short journeys to work everyday and now the car has failed only 1 month later which doesn’t make sense. 

Can people post fixes for this or links for these trickle chargers and how they work  or any other recommendations that may work  I have lost all confidence in the car starting every day. I have booked it in for Toyota to check it out but just wanting some answers or advice whilst waiting for my appointment. Many thanks for any advice.

 

[O.W.L.]

If you park your car somewhere that has daylight, a solar powered charger is helpful, plugged into the EOBD socket underneath the steering wheel.

 

I use this AA charger and plug it in every time I park the car. I've not had a problem like yours since I started using it.  https://www.amazon.co.uk/Powered-Battery-Charger-Caravan-Package/dp/B07P7C6QLD/ref=sr_1_5?crid=2GCTO0L4F2UWV&keywords=aa+12v+solar-powered+car+battery+charger&qid=1682946000&sprefix=AA+solar+powered+charger%2Caps%2C75&sr=8-5

[Big_D]

I have the same AA Solar charger as @O.W.L. but have not used it yet. I had an instance once with my 2020 C-HR where it wouldn;t start. That was over the winter of 2021 where I didn't use the car for about a week. I managed to get it started with the help of a booster Battery and have never had any issues since. I have since part exchanged it for a new C-HR, and am hoping the Battery will be fine on the new one. 

It may be that the Battery is faulty, and if you bought your C-HR from a Dealer, they may be prepared to replace the battery. After all, you've only had the car since February this year.

[philip42h]

5 hours ago, 96McKJ91 said:

I use the car most of the week normally to work Monday to Friday 10 min - 30 min journey each time and occasionally over the weekend - I have only had the car since February 2023 and have done a round trip of 5 hours out and 5hrs back in march but now back to doing my short journeys to work everyday and now the car has failed only 1 month later which doesn’t make sense. 

As you say, this doesn't make sense ... 😉

If you have read the various posts, you will know that Toyota hybrids have a relatively modest sized 12V auxiliary Battery which will run flat if the car is not used for an extended period of time. Toyota's advice is that the should be in Ready mode for a minimum of 60 minutes per week to maintain the state of charge of the auxiliary Battery - i.e. put back as much charge as it will use while standing idle.

A 10 minute journey to work and a 10 minute journey home again 5 days a week would amount to 100 minutes in Ready mode and, on that basis, you shouldn't have any issues. And occasional longer trips will ensure that the auxiliary Battery gets fully charged from time to time. So what you are reporting doesn't make sense ...

Possible explanations include:

• A faulty battery - such things happen and a visit to the dealer should diagnose and resolve the problem.
• Operator error - such as leaving the car in Accessory mode to listen to the radio while waiting etc.. The auxiliary battery is drained but not charged while in Accessory mode so it is best not used. This is obvious once you realise but a bit of a gotcha that has caught out one or two owners.
• A non-standard accessory that drains the battery while the car is Off. The obvious example might be a owner-fitted dash cam that is wired 'always on' - dealer fitted dash cams are wired to be on only in Ready mode.
• Some other 'fault' that causes the battery to be drained when it shouldn't ...

So the next step is to understand why this is happening ...

It may them be advantageous to periodically top-up the auxiliary battery using a smart charger, use a solar powered charger and/or carry a small jump start pack so that you can easily get back into Ready mode if the auxiliary battery does run low ...

[Trewithy]

I'd say it is time for a new Battery.  Once it has gone totally flat it is damaged goods and you can charge it as much as you like but it will never retains its charge as well as it used to.  Changing your Battery is a lot cheaper than changing your car and might just restore your confidence in the vehicle.  It is worth a try.

[Cyker]

Since it's purchased so recently, make it the dealer's problem to sort it out. I suspect the others are right and it just needs a new Battery tho'.

 

[Gray86]

I have one of these: https://www.amazon.co.uk/CTEK-MXS-5-0-Reconditions-Motorcycle/dp/B00FC42HAA

it has brought back several neighbours batteries from the dead, and maintained both mine and my wife’s cars for the last 3 years. In a world of EVs & hybrids with small 12v batteries, it’s pretty much a necessity unless you do a lot of miles. 
 

I top mine up every couple of months in warmer weather, and every couple of weeks in winter (dependant on usage). Doesn’t take long to charge a small Toyota hybrid 12v Battery at all. 

[96McKJ91]

Thanks for all the info and advice given from everyone. 
I will buy one of those AA solar charges as I managed to get the car jump started again today and then drove it for 2 hours - which involved visiting my local Toyota dealer, who were helpful enough and recommended I run it for at least an hour with the air on on full blast, to make the engine kick in (sorry not savvy with the right technical lingo - but apparently when it makes a noise the auxiliary Battery will then be getting a charge) and to do this if I wasn’t going to drive it to recharge the Battery - they also said the AA solar charger had now been tested and approved for use by Toyota so probably a good buy to stop this issue for now. 
it is booked in for diagnostic testing and the guys at Toyota said they will probably change the Battery and hopefully this will stop the issue 🤞 - really though Toyota being a respected and trusted brand should have addressed this issue a long time ago, as it is not fit for purpose, as the guys said it had been a problem with the CHR and another model, I forgot which one he said though.

so much for saving the environment, running the car when you shouldn’t need too seems like a false environmental economy 😔 

[96McKJ91]

9 hours ago, O.W.L. said:

If you park your car somewhere that has daylight, a solar powered charger is helpful, plugged into the EOBD socket underneath the steering wheel.

 

I use this AA charger and plug it in every time I park the car. I've not had a problem like yours since I started using it.  https://www.amazon.co.uk/Powered-Battery-Charger-Caravan-Package/dp/B07P7C6QLD/ref=sr_1_5?crid=2GCTO0L4F2UWV&keywords=aa+12v+solar-powered+car+battery+charger&qid=1682946000&sprefix=AA+solar+powered+charger%2Caps%2C75&sr=8-5

Thanks O.W.L.

I think this maybe the one that Toyota has now approved- I think this will be my next purchase as I am scared to switch the car off after driving now as don’t want to keep getting stranded and awaiting breakdown service. On the plus side I taught myself how to jumpstart the car today 🤣, so small positive wins 😛 

[96McKJ91]

8 hours ago, Big_D said:

I have the same AA Solar charger as @O.W.L. but have not used it yet. I had an instance once with my 2020 C-HR where it wouldn;t start. That was over the winter of 2021 where I didn't use the car for about a week. I managed to get it started with the help of a booster battery and have never had any issues since. I have since part exchanged it for a new C-HR, and am hoping the battery will be fine on the new one. 

It may be that the battery is faulty, and if you bought your C-HR from a Dealer, they may be prepared to replace the battery. After all, you've only had the car since February this year.

Thanks yep will be getting this one I think. 
Bought car from Cazoo and even though still under their warranty - lo and behold Battery is not covered, not amused is putting it mildly!!! 
On the plus side the service book does have all the relevant service stamps from Toyota dealers so hopefully it may come under their warranty who knows - I assuming it’s going to cost me but if a warranty kicks in somewhere I’ll be super happy  thanks again

 

[Corollanutter]

15 minutes ago, 96McKJ91 said:

Thanks for all the info and advice given from everyone. 
I will buy one of those AA solar charges as I managed to get the car jump started again today and then drove it for 2 hours - which involved visiting my local Toyota dealer, who were helpful enough and recommended I run it for at least an hour with the air on on full blast, to make the engine kick in (sorry not savvy with the right technical lingo - but apparently when it makes a noise the auxiliary battery will then be getting a charge) and to do this if I wasn’t going to drive it to recharge the battery - they also said the AA solar charger had now been tested and approved for use by Toyota so probably a good buy to stop this issue for now. 
it is booked in for diagnostic testing and the guys at Toyota said they will probably change the battery and hopefully this will stop the issue 🤞 - really though Toyota being a respected and trusted brand should have addressed this issue a long time ago, as it is not fit for purpose, as the guys said it had been a problem with the CHR and another model, I forgot which one he said though.

so much for saving the environment, running the car when you shouldn’t need too seems like a false environmental economy 😔 

As far as I know, there is no need to run the “air” or any other system on the car to ensure the 12v Battery is getting charged. The 12v Battery is charged from the HV Battery via the inverter on a demand basis, the ICE will automatically cut in when the HV battery needs topping up. So, if your 12v battery is low, just having the car in ready mode will ensure a charge to the battery. Turning on other demands (Such as AC) will make the ICE run more frequently and cost you more money. Just make sure your car is secure when leaving it in ready mode!  Happy to be corrected if I’m wrong! 

[96McKJ91]

5 hours ago, philip42h said:

As you say, this doesn't make sense ... 😉

If you have read the various posts, you will know that Toyota hybrids have a relatively modest sized 12V auxiliary battery which will run flat if the car is not used for an extended period of time. Toyota's advice is that the should be in Ready mode for a minimum of 60 minutes per week to maintain the state of charge of the auxiliary battery - i.e. put back as much charge as it will use while standing idle.

A 10 minute journey to work and a 10 minute journey home again 5 days a week would amount to 100 minutes in Ready mode and, on that basis, you shouldn't have any issues. And occasional longer trips will ensure that the auxiliary battery gets fully charged from time to time. So what you are reporting doesn't make sense ...

Possible explanations include:

• A faulty battery - such things happen and a visit to the dealer should diagnose and resolve the problem.
• Operator error - such as leaving the car in Accessory mode to listen to the radio while waiting etc.. The auxiliary battery is drained but not charged while in Accessory mode so it is best not used. This is obvious once you realise but a bit of a gotcha that has caught out one or two owners.
• A non-standard accessory that drains the battery while the car is Off. The obvious example might be a owner-fitted dash cam that is wired 'always on' - dealer fitted dash cams are wired to be on only in Ready mode.
• Some other 'fault' that causes the battery to be drained when it shouldn't ...

So the next step is to understand why this is happening ...

It may them be advantageous to periodically top-up the auxiliary battery using a smart charger, use a solar powered charger and/or carry a small jump start pack so that you can easily get back into Ready mode if the auxiliary battery does run low ...

Thanks for this full explanation Philip42h - I have no idea if I have left anything on but have now taken to switching the air on off when I know I’m parked up for the day whilst at work or overnight - making sure the heated seat is switched off - and turning off the volume on the screen if I knew how to turn the touchscreen off I would do that too. Looked at how to turn off lights but don’t think I can and the automatic windscreen wipers but again not sure how to do it and to be quite honest I am a little annoyed I have to take all this into consideration. I don’t own a dash cam, so that’s not an issue and I unplug my car charger if I’m not using it. I think Toyota, once they realised there was an issue with short journeys discharging their batteries or items  in the car that may drain the Battery that they have installed then I think they should have recalled the cars and replaced the Battery for something that wouldn’t fail so easily. 
I’m hoping it’s a faulty Battery and the issue is resolved with a battery that can hold is own under the typical usage time people drive for.

I do appreciate all your advice and hopefully Toyota will resolve this problem easily many thanks.

[96McKJ91]

9 hours ago, Corollanutter said:

As far as I know, there is no need to run the “air” or any other system on the car to ensure the 12v battery is getting charged. The 12v battery is charged from the HV battery via the inverter on a demand basis, the ICE will automatically cut in when the HV battery needs topping up. So, if your 12v battery is low, just having the car in ready mode will ensure a charge to the battery. Turning on other demands (Such as AC) will make the ICE run more frequently and cost you more money. Just make sure your car is secure when leaving it in ready mode!  Happy to be corrected if I’m wrong! 

Yes I thought this too and the first time I left it running I switched everything off. I must say I was surprised when they said leave it on. These guys were the salesmen though so not the service guys who knows I’ll probably get other advice from the service centre when I see them later this week. 
the salesman also said maybe hybrids not for me if I’m not driving far enough ( what a crock) and then tried to sell me a full petrol car 😳🤣

I really don’t know what to believe anymore!!

I’ll keep all posted if I get a good resolution or not!!

[96McKJ91]

5 hours ago, Trewithy said:

I'd say it is time for a new battery.  Once it has gone totally flat it is damaged goods and you can charge it as much as you like but it will never retains its charge as well as it used to.  Changing your battery is a lot cheaper than changing your car and might just restore your confidence in the vehicle.  It is worth a try.

Yep totally agree and hope Toyota think the same as they kept telling me at the service centre that it’s basically my fault as I don’t drive far enough and not a Battery issue but it is. I’ve been driving for over 30 years and have only ever had this happen with a very old car that the alarm had started to put a drain on even a newly installed Battery. The poor old Zamora had had 14/15 years of service before it gave me any issues - not like this little whipper snapper at only 4 yrs old and only owned by me for a couple of months 😂!!

[Corollanutter]

7 hours ago, 96McKJ91 said:

Thanks for this full explanation Philip42h - I have no idea if I have left anything on but have now taken to switching the air on off when I know I’m parked up for the day whilst at work or overnight - making sure the heated seat is switched off - and turning off the volume on the screen if I knew how to turn the touchscreen off I would do that too. Looked at how to turn off lights but don’t think I can and the automatic windscreen wipers but again not sure how to do it and to be quite honest I am a little annoyed I have to take all this into consideration. I don’t own a dash cam, so that’s not an issue and I unplug my car charger if I’m not using it. I think Toyota, once they realised there was an issue with short journeys discharging their batteries or items  in the car that may drain the battery that they have installed then I think they should have recalled the cars and replaced the battery for something that wouldn’t fail so easily. 
I’m hoping it’s a faulty battery and the issue is resolved with a battery that can hold is own under the typical usage time people drive for.

I do appreciate all your advice and hopefully Toyota will resolve this problem easily many thanks.

There is no need to switch off the items you mention. They are all powered down when you switch the car off. Pretty much the only items left powered will be the smart entry system (or door locking system) the alarm and the ECU controlling the wireless connectivity. All of these SHOULD have very low current draw. A permanently powered dash cam would be by far the biggest culprit - but you don’t have one of those. 

[philip42h]

9 hours ago, Corollanutter said:

As far as I know, there is no need to run the “air” or any other system on the car to ensure the 12v battery is getting charged. The 12v battery is charged from the HV battery via the inverter on a demand basis, the ICE will automatically cut in when the HV battery needs topping up. So, if your 12v battery is low, just having the car in ready mode will ensure a charge to the battery. Turning on other demands (Such as AC) will make the ICE run more frequently and cost you more money. Just make sure your car is secure when leaving it in ready mode!  Happy to be corrected if I’m wrong! 

What you say is entirely correct, but, as I understand ...

Under 'normal' circumstances the DC-DC converter will supply the ~13V required to run the electrical systems leaving the auxiliary Battery pretty much nothing to do. This will very slowly trickle charge the auxiliary Battery but not much more.

When the demand on the 12V system rises significantly or the auxiliary Battery appears significantly discharged the DC-DC converter switches into charge mode and ups the output to 14V+ so as to recharge the auxiliary battery. So, perversely, increasing the demand on the auxiliary battery will result in it being charged more quickly.

Or, at least, that's how I understand it. 😉

And, obviously, this is a somewhat daft approach - if you suspect that the 12V auxiliary battery may be 'low' it would make more sense to top it up with a smart charger if you can ...

[philip42h]

9 hours ago, 96McKJ91 said:

the salesman also said maybe hybrids not for me if I’m not driving far enough ( what a crock)

Based on what you have said already, that is such a crock. Your daily commute plus occasional longer journeys is more than enough to keep a good Battery topped up. There's nothing wrong with the design in that respect and a hybrid will suit you just fine.

It's not a question of not driving "far enough" but rather not being in Ready mode "long enough" - the target being >= 60 minutes each week. You do that easily.

Someone who leaves the car parked-up and unused for weeks on end may well have problems with the auxiliary Battery. That usage profile wouldn't suit a hybrid.

[Corollanutter]

8 hours ago, philip42h said:

What you say is entirely correct, but, as I understand ...

Under 'normal' circumstances the DC-DC converter will supply the ~13V required to run the electrical systems leaving the auxiliary battery pretty much nothing to do. This will very slowly trickle charge the auxiliary battery but not much more.

When the demand on the 12V system rises significantly or the auxiliary battery appears significantly discharged the DC-DC converter switches into charge mode and ups the output to 14V+ so as to recharge the auxiliary battery. So, perversely, increasing the demand on the auxiliary battery will result in it being charged more quickly.

Or, at least, that's how I understand it. 😉

And, obviously, this is a somewhat daft approach - if you suspect that the 12V auxiliary battery may be 'low' it would make more sense to top it up with a smart charger if you can ...

You are most probably correct Philip, however when I look at the charge and voltage status from my Battery monitor, if the Battery is partly discharged (such as after a few days resting) I see that the Battery is getting a fairly hefty charge (approx 14.35V) for at least an hour - then the charge voltage drops when the battery is reaching 80-90% charge. However, and as you also say, the most economic way of charging is a mains powered smart charger. 

[96McKJ91]

8 hours ago, philip42h said:

Based on what you have said already, that is such a crock. Your daily commute plus occasional longer journeys is more than enough to keep a good battery topped up. There's nothing wrong with the design in that respect and a hybrid will suit you just fine.

It's not a question of not driving "far enough" but rather not being in Ready mode "long enough" - the target being >= 60 minutes each week. You do that easily.

Someone who leaves the car parked-up and unused for weeks on end may well have problems with the auxiliary battery. That usage profile wouldn't suit a hybrid.

Thanks for this explanation as the way they are saying is that I have to drive for longer than 40 mins in one journey for the Battery to charge 😔

since I’ve had this car I have tried to be gentle with it to see how often I can get the ev symbol to kick in (sad I know, but it amused me!) would this have affected it plus I haven’t really been using the air con at all would my economical style of driving created an issue??  Silly question but the thought crossed my mind and I had to ask. 😆

[Corollanutter]

21 minutes ago, 96McKJ91 said:

Thanks for this explanation as the way they are saying is that I have to drive for longer than 40 mins in one journey for the battery to charge 😔

since I’ve had this car I have tried to be gentle with it to see how often I can get the ev symbol to kick in (sad I know, but it amused me!) would this have affected it plus I haven’t really been using the air con at all would my economical style of driving created an issue??  Silly question but the thought crossed my mind and I had to ask. 😆

The way you drive the car has a negligable effect on the way the 12V Battery charges. It is almost purely time based. Use of the AC (IMHO) makes very little difference to economy - but turning it on can make a big difference to your comfort and state of mind :-)  Using the heater though can make a much larger difference to economy (the ICE is running at times purely to heat the car interior). 

 

[TonyHSD]

I believe it is slightly different the energy flow.
The 12v Battery powers up everything directly with exception of AC compressor and the traction motor.
The inverter/ converter otoh supply up to 15v to recharge the small 12v Battery, the power supply comes from the bigger 200v hybrid Battery, when this battery gets low the engine kicks in to recharge it.
The whole process is similar to the standard car with ice and alternator. If your 12v battery is completely dead , shorted or any other failure the whole system will become inactive and you won’t be able to run the car at all. 
When I test my car as soon as I start the car ( in ready mode ) I got 14.7v measurements taken from the battery terminals, with or without any electrical consumers. When checking with Carista app over the phone I read 15v as seen by the ecu. 
The only difference from other members explained is that the 12v battery always power up and supply all the system in the car and inverter is charging this battery. 
AC does affect the efficiency a bit especially in hot days and when driving in town because it drains the hybrid battery faster and reduces the ev time. The heater does affect efficiency too, the engine will run more frequently and for longer. Good to have these two ON according to the season because the cabin temperature also maintains the hybrid battery temperature. Battery chemistry does like ambient temperatures all the time 15-25C° 👍

[Big_D]

1 hour ago, 96McKJ91 said:

since I’ve had this car I have tried to be gentle with it to see how often I can get the ev symbol to kick in (sad I know, but it amused me!) would this have affected it plus I haven’t really been using the air con at all would my economical style of driving created an issue??

This is exactly the way I drive and it has had no effect on my 12v Battery in either of my C-HRs

[philip42h]

On 5/1/2023 at 1:00 PM, 96McKJ91 said:

I have only had the car since February 2023 ...

So the car was three or for years old when new to you. How many miles had it done? And have you any idea how long it was sat around before you acquired it?

We'll probably never know for sure but it seems perfectly possible that the auxiliary Battery has 'gone bad' and this is nothing at all to do with what you have done with the car but due to the circumstances of its use and storage in it's former life.

[Big_D]

I think it is a bad Battery, rather then the way it is being driven

[96McKJ91]

11 hours ago, Big_D said:

This is exactly the way I drive and it has had no effect on my 12v battery in either of my C-HRs

All this is good to know as I don’t want Toyota to fob me off with “it’s my own fault” and am glad to hear my driving hasn’t been the issue. Many thanks