Dead Battery Would Not Charge

[roudiva]

Hi! I need advice regarding our new hybrid (CH-R 2021). We left the car without driving it for about 3 weeks, and when I attempted to start it, the Battery had given out. We purchased TOPDON JS2000 power bank and attempted to charge it with it. Upon connecting and pressing "Boost", the car lights up, but we are unable to get the engine to run. After a boost attempt, the electricity would remain on for about 30 seconds and then shut off. We did this a few times, after following the power bank instructions for safety, and got to a point where there's minimal electricity on the dashboard that doesn't turn off by itself, but we're still unable to start the engine. Can anyone advice what the root cause could be and what we need to do? At the moment, we're charging the power bank again to give it another try in a few hours. It does seem like we're making progress in terms of getting the Battery charge, but it is so minimal it won't get the engine to run.

[Harters]

I am not sure from your post if you are trying to charge the car with the power bank or start it.  A portable power bank is only designed to get your car started and not to charge the Battery. 

The one I have, I connect it to the 12v Battery, it does a quick self check to make sure it's connected correctly, then you start the car.  Once the car is started you should remove the power bank.

A power bank should have no trouble starting the C-HR as its only needs enough juice to get the computers running.  I have successfully started a 2.0 diesel Golf with mine with no trouble at all.

I hope this helps.

[Mooly]

52 minutes ago, roudiva said:

Can anyone advice what the root cause could be and what we need to do?

The root cause (and this is backed up by all the many posts on 12v batteries discharging across all the Hybrid models) is that Toyota have not adequately accounted for background current draw and how this causes deterioration of the 12v Battery. I would class it as a major design fault.

There is also a suspicion that if the batteries go flat between vehicle manufacture and delivery to the customer then the Battery is already starting from a deteriorated state. A heavy duty charger will put some life back into it but it soon fails again.

Once a Battery of this type has been discharged or been in a continually low state of charge then it can not be recovered. Unfortunately I think you will need a new battery.

[Bper]

I was wondering if anyone has addressed this with Toyota regarding the Battery issue and if so what was their response.

[roudiva]

48 minutes ago, Harters said:

I am not sure from your post if you are trying to charge the car with the power bank or start it.  A portable power bank is only designed to get your car started and not to charge the battery. 

The one I have, I connect it to the 12v battery, it does a quick self check to make sure it's connected correctly, then you start the car.  Once the car is started you should remove the power bank.

A power bank should have no trouble starting the C-HR as its only needs enough juice to get the computers running.  I have successfully started a 2.0 diesel Golf with mine with no trouble at all.

I hope this helps.

Thank you very much! The condition I am describing is after using a Topdon power bank for jump start - lights on but power still insufficient to get the engine running. If it doesn't work after one last attempt, I'm afraid we will need a new Battery. Thanks again for sharing your experience. 

[roudiva]

32 minutes ago, Mooly said:

The root cause (and this is backed up by all the many posts on 12v batteries discharging across all the Hybrid models) is that Toyota have not adequately accounted for background current draw and how this causes deterioration of the 12v battery. I would class it as a major design fault.

There is also a suspicion that if the batteries go flat between vehicle manufacture and delivery to the customer then the battery is already starting from a deteriorated state. A heavy duty charger will put some life back into it but it soon fails again.

Once a battery of this type has been discharged or been in a continually low state of charge then it can not be recovered. Unfortunately I think you will need a new battery.

Your explanation really helps. From what I am seeing, we need a new Battery. Thank you for your time!

[philip42h]

2 hours ago, roudiva said:

We left the car without driving it for about 3 weeks, and when I attempted to start it ...

So, it's a known feature that if we leave our hybrids standing, unused, for too long the voltage in the auxiliary Battery will drop to a point at which the car won't go into Ready mode when we ask it to.

If the auxiliary Battery is only marginally depleted, a low-capacity jump start pack will provide sufficient additional power to get the car into Ready mode - and from there the traction Battery and engine will recharge the auxiliary battery.

If the auxiliary battery is in a more discharged state, the next thing to try is to recharge it with a smart charger - i.e. recharge it 'overnight'. When all is said and done, that's what Toyota will do when testing the auxiliary battery. If it holds a decent state of charge 'in the morning' you are then good to go - at least in the near term.

If the auxiliary battery is too far gone to be recharged by a smart charger, you will need a new battery.

[roudiva]

Thank you, Philip! We'll give it another try following your advice.

[roudiva]

Putting the car in maintenance mode did the trick! The engine started (after another 2 boosts with the power bank jump starter Topdon JS2000 ) and we were able to drive to... the nearest Toyota shop :)) Tomorrow we will have the battery's health checked and see if we need a new one. Thank you all again for your support and guidance!

And here is a helpful video of how to put the hybrid in maintenance mode which I have never heard of before:

 

 

 

[STR61]

Every summer for the last 4 years the start Battery on my CH-R went flat at least 3 times. The problem is that, if you drive the car to maximise efficiency (running the car in eco mode), the engine runs for a minimal time. This means that the start Battery doesn't get any charge; however, the headlights are on, the air con may be on, and the radio may be on which all discharge the Battery. On my 35min journey home from work the engine is running for less than 10 minutes, so that is all the charge the start battery is getting. If you live in a hilly area as I do, the electric motor can get the car up minor gradients with just a little assistance from the engine; going downhill the engine is off. I don't think Toyota considered this problem when designing the car. I ended up buying a trickle charger, and stick this on frequently to ensure the battery stays charged. I'm afraid this is just a design fault that you have to live with. You can always run around in Sports mode if you don't mind a lower mpg.

[philip42h]

23 minutes ago, STR61 said:

Every summer for the last 4 years the start battery on my CH-R went flat at least 3 times. The problem is that, if you drive the car to maximise efficiency (running the car in eco mode), the engine runs for a minimal time. This means that the start battery doesn't get any charge; however, the headlights are on, the air con may be on, and the radio may be on which all discharge the battery. On my 35min journey home from work the engine is running for less than 10 minutes, so that is all the charge the start battery is getting. If you live in a hilly area as I do, the electric motor can get the car up minor gradients with just a little assistance from the engine; going downhill the engine is off. I don't think Toyota considered this problem when designing the car. I ended up buying a trickle charger, and stick this on frequently to ensure the battery stays charged. I'm afraid this is just a design fault that you have to live with. You can always run around in Sports mode if you don't mind a lower mpg.

A few errors here Stephen:

1. Your C-HR doesn't have a starter Battery (or a starter motor) - just a 12V auxiliary Battery.
2. The auxiliary Battery isn't charged via the engine (or an alternator). The auxiliary battery is charged from the traction battery via the DC-DC converter. The traction battery is, of course, charged via the engine etc..
3. The mode that you choose to drive in has absolutely no bearing on the state of charge of the auxiliary battery.

But having a smart / trickle charger isn't a bad idea ... 😉

[TonyHSD]

44 minutes ago, STR61 said:

Every summer for the last 4 years the start battery on my CH-R went flat at least 3 times. The problem is that, if you drive the car to maximise efficiency (running the car in eco mode), the engine runs for a minimal time. This means that the start battery doesn't get any charge; however, the headlights are on, the air con may be on, and the radio may be on which all discharge the battery. On my 35min journey home from work the engine is running for less than 10 minutes, so that is all the charge the start battery is getting. If you live in a hilly area as I do, the electric motor can get the car up minor gradients with just a little assistance from the engine; going downhill the engine is off. I don't think Toyota considered this problem when designing the car. I ended up buying a trickle charger, and stick this on frequently to ensure the battery stays charged. I'm afraid this is just a design fault that you have to live with. You can always run around in Sports mode if you don't mind a lower mpg.

Hi, 

as pointed already het there is some misunderstanding. Toyota hybrids does not need engine to be running to recharge the 12v Battery. They only need to be set in ready mode and the hybrid system will recharge the 12v Battery. Engine only chargers the hybrid Battery. 

[STR61]

Tony/Philip

Thanks for your replies and for clearing that up for me, just strange how the car goes completely dead sometimes, where we have to use the key to open the door, as there is not even enough power to open it via the touch sensor on the handle.

Cheers

Steve 

[Roy124]

Returning to Iva's OP.  It appears that his CHR is new to him.  The Battery usage and condition over the previous 3 years is unknown. 

When I exchanged my Corolla I certainly would not tell the dealer that the Battery had been flat.   Equally, when the dealer sells the car on he is not going to tell the buyer either.

When I had my problem the Battery was replaced with a larger capacity one.  There was no entry made in the Service history.

Getting the dealer to check the battery is the best course of action.

[ritayaris]

On 10/12/2023 at 11:59 AM, Bper said:

I was wondering if anyone has addressed this with Toyota regarding the battery issue and if so what was their response.

I have had same problem with 2020 Yaris. My 3rd Yaris and never had this problem before. Toyota kept car overnight twice and checked and charged Battery and said nothing wrong with it. Battery went flat again this week after not being used for 2 week holiday. It started with jump leads. This has happened 5 times over past year and had to get AA out. Very inconvenient and I am considering selling car and buying another make.

[Bper]

Hi Rita,

This is such a shame that you are considering selling the car due to the Auxiliary Battery problem. I can imagine how frustrating it is for this to happen 5 times.

Has Toyota given you any advice on what to do to prevent this happening. Whilst I don't have a Hybrid and do not suffer from this problem I am interested in what Toyota plans are to resolve this very common issue with this Aux Battery discharge. 

Perhaps other members can give you the benefit of their experience to help prevent this from happening to you.

It shouldn't get to a point where you should have to consider selling the car.😊

[barriechris@aol.com]

I had this problem with my 2020 C-HR Excel. It has done 35k miles, so it s not due to lack of use. Toyota main dealer changed the Battery free of charge. I will probably change the car next year. Does anyone know whether the new C-HR has the same system, and therefore may have the same 12v Battery problems. Has Toyota done anything to the new model to resolve this issue?

[Paul john]

26 minutes ago, barriechris@aol.com said:

I had this problem with my 2020 C-HR Excel. It has done 35k miles, so it s not due to lack of use. Toyota main dealer changed the battery free of charge. I will probably change the car next year. Does anyone know whether the new C-HR has the same system, and therefore may have the same 12v battery problems. Has Toyota done anything to the new model to resolve this issue?

Nope same issue as a 12v is considered a consumable item. Same as tyres and brakes. 
The MyT app shows the status of the 12v for peace of mind but if you do not drive the car sufficiently to keep it in charge it will eventually fail.

Basic physics.  

[Dala]

Interesting how physics changes.  30 years ago I stopped the car for half a year and there was no problem.

[Big_D]

But, 30 years ago did you have the same electronics that modern vehicles have, putting a drain on the Battery?

Probably not. Today, most modern cars have an alarm immobiliser which does drain the Battery over time.

[Roy124]

Rita, your problems point to a very simple cause.

Whenever the Battery goes flat permanent damage occurs.  With each successive flat event the level of damage increases.

After the third failure subsequent failures will occur more frequently.