12v Battery, the Achilles heel

[paulrnx]

6 minutes ago, Herbie said:

Surely people wouldn't be so silly?

Now with that, we are in complete agreement. Having said that though, as Colin Barber said earlier in this topic, Toyota have been in the hybrid business for a long time and they must think that it's acceptable or they would have changed it by now.

We’re not really discussing whether Lexus/Toyota think it’s acceptable. We’re talking about whether it is acceptable to owners who are suffering flat 12v batteries or who are taking steps to prevent it or who are concerned this may happen. The two things are different. I’m just surprised. It clearly is an achilles heel.

[NemesisUK]

Sorry but I think there is no special requirements for owning/driving a hybrid.

The car is designed and configured/programmed to be as efficient as possible when driven 'normally'.

As with any make model or type of car, it's design efficiencies can be altered for better or worse by driving styles.

Regarding long intervals of non-use, I think Lexus are no different from many other marques. My AMG had to be on a trickle charger if left more than a week. Many models now come with factory fitted charge points.

Lexus/Toyota have been selling hybrids for many a year now and clearly there has been no significant feedback complaining of poor 12v Battery life

 

[Brechin Slate]

2 minutes ago, paulrnx said:

I’m just surprised. It clearly is an achilles heel.

And on that I think we all agree

[paulrnx]

4 minutes ago, Herbie said:

But this is my whole point Paul - it's not the car's fault, it's their own fault for not researching everything they can about a machine that's not like any other they've ever driven.

This is the society we've made for ourselves - always someone else's problem/fault, never our own.

I think we’re just going to have to disagree on this one. I think it’s a poor design and clearly an Achilles heel.

[Herbie]

4 minutes ago, paulrnx said:

I think it’s a poor design and clearly an Achilles heel.

So do I.

All I'm saying is that a lot of heartache, hassle and grief that some people seem to have could be avoided if they took responsibility, but if they prefer to make life harder for themselves then that's fair enough 😊

[Spacewagon52]

A very interesting thread chaps. Had not used my RX300 for ........... a while ............ Battery flat. Used a smart charger overnight - now shows fully charged. If the Battery will not fully charge then I would suspect it is on its way out and change it.

If I leave my cars for more than a week somewhere other than home, I will buy a jump starter as has been suggested.

[Ala Larj]

Sorry to be a bit naive but I’ve no knowledge of electrics. My understanding from this thread is that the Battery in a hybrid is not as powerful as a normal Battery. I get confused about volts and amps. It appears that I have a Battery of 12v but less amps. If I were to replace my Battery with one with more amps would that solve the problem of having to start the car once a week to keep it topped up?

[Herbie]

15 minutes ago, Ala Larj said:

Sorry to be a bit naive but I’ve no knowledge of electrics. My understanding from this thread is that the battery in a hybrid is not as powerful as a normal battery. I get confused about volts and amps. It appears that I have a battery of 12v but less amps. If I were to replace my battery with one with more amps would that solve the problem of having to start the car once a week to keep it topped up?

It would definitely last longer but would still go flat eventually, so it's a bit of a workaround rather than a cure.

I don't know where the 12V Battery is located in your car but if you were thinking of doing this then the most important thing is to make sure that the bigger Battery will physically fit in whatever space you have, whilst still allowing t to be clamped down securely.

As for the Battery itself and your slight confusion, I'll try to explain (but it is late and I've had a few beers ).

For hybrids, the most important parameter is the capacity of the Battery, measured in Amp Hours (Ah). As an example, a Battery rated at 50Ah means that it could supply 50A for one hour or 25A for two hours and so on, before it fully discharges.

Modern cars will always be pulling power from the Battery in order to keep the clock at the right time; keep the radio presets in memory; keep the alarm activated and armed and so on, even when the car is locked up in the garage for the night and you're fast asleep in bed. This is called the quiescent current and official figures should be available from the manufacturers but I've never seen them if they are. As a general rule of thumb, a quiescent current of 50mA (0.05A) is considered to be about normal.

So, we now have the capacity of the Battery (the one on my RX450h is 51Ah, whereas the ones in my previous 'petrol only' cars have been 75Ah and above) and we know that, with nothing else on and no faults, the car should draw 50mA. If we assume that my Battery is brand new and fully charged, the capacity divided by the drain will give us the time to full discharge, so 51Ah/0.05A = 1,020 hours (42.5 days or 6 weeks) from fully charged to fully discharged. However, for the purposes of starting the car, it will fail long before that full discharge at six weeks. Remember as well, that for the purpose of this discussion we assumed a brand new and fully charged Battery, ie, 'perfect conditions' - if the Battery isn't perfect then that will also reduce the time span.

Let's say that a bigger Battery will physically fit and that it has a capacity of 80Ah instead of the current one at 51Ah, the calculation now becomes 80Ah/0.05A = 1,600 hours (66.66 days or 9.52 weeks) under perfect conditions, but again, reality will be different.

Right, I hope that's helped but I'm now off to bed 😊

[200h]

in the GS the Battery is in the near side rear quarter inside the boot,

the 12v Battery is the Achilles heel of all vehicles, take too much

out of the Battery and your vehicle wont start, the issue is how quick

you get to that point of having a non starter, but as long as your aware

of what can happen then it shouldn't be an issue.

 

[PaulWhitt20]

So the moral of the story is. Its a lovely car, find an excuse to drive it every week.

🙃

 

[Herbie]

18 hours ago, NemesisUK said:

Sorry but I think there is no special requirements for owning/driving a hybrid.

The car is designed and configured/programmed to be as efficient as possible when driven 'normally'.

The more I think about this, the more I disagree.

• You need to know that there is high voltage around and you definitely don't go ferreting about in places where you could be killed unless you have the specialist knowledge and equipment
• You need to know not to just buy any can of refrigerant off the shelf at Halfords if the aircon needs topped up. Using the wrong oil can cause thousands of pounds-worth of damage
• You may not need to know but it's perhaps a good idea if you do, that there is no alternator, no starter motor and that things like power steering are electric instead of hydraulic
• You need to know that you can't drive it for more than a mile or two on Battery alone if you run out of petrol (some people seem to think that the Battery is a substitute for the petrol engine)
• You need to know that running out of petrol is really a very bad thing to do
• You need to know that if you do run out of petrol then you need a minimum of 10 litres in the tank before it will restart
• You need to know that if you unsuccessfully try to restart it more than three times (if I recall correctly) then the hybrid system can lock you out and you have to call the dealer to reset it
• You need to know that if the traction Battery goes flat, you need to call the dealer or some other specialist to get you going because the AA, RAC etc., certainly can't

These are all things that will be completely new and unknown to you if you've only ever driven petrol-engined cars before and is why people need to do some research before buying.

Oh, and you need to know that the 12V Battery is undersized and can go flat rather quickly  🙂

[NemesisUK]

Well, I can't disagree with any of what you post there Herbie.

I managed to survive my first year of driving a hybrid without incident but then I have an inquiring mind and quickly discovered many of these 'quirks'

I think it quite sad that these days many, perhaps even, most buyers are more concerned with the audio system and whether their phone will connect with it.....

[Spacewagon52]

27 minutes ago, NemesisUK said:

I think it quite sad that these days many, perhaps even, most buyers are more concerned with the audio system and whether their phone will connect with it.....

That seems to be a common thread on this site. Age related no doubt but still a bit mystifying to me.

 

Reliability, refinement, longevity, comfort would all come before  - whether my Nokia 3310 would connect to the CD player.

[mikey2001]

10 hours ago, PaulWhitt20 said:

So the moral of the story is. Its a lovely car, find an excuse to drive it every week.

🙃

 

That's certainly what I try and do to keep my 12v Battery charged up. I know a lot of people haven't be able to use their cars as much during this past year or so (myself included as I've been working at home, lockdown etc.), but I generally drive 'the long way round' to any places I need to go to, e.g. food shopping. Helps to charge the Battery up and I'm still able to enjoy driving the car 🙂

[Maxz]

Still doing the monthly charge since the original post in April, always plenty of juice in the 12v. When lockdown is lifted and you’re off on that long awaited holiday, always pays to do that extra recharge the day before heading off to the airport. Charging via the engine bracket and jump start positive means you can still close the bonnet and arm the alarm whilst charging if the car is parked outside. I wouldn’t risk it when raining as the fuse box cover is off but in theory the water should still not ingress to this part of the engine bay anyway.

 

[royoftherovers]

23 hours ago, Spacewagon52 said:

A very interesting thread chaps. Had not used my RX300 for ........... a while ............ battery flat. Used a smart charger overnight - now shows fully charged. If the battery will not fully charge then I would suspect it is on its way out and change it.

If I leave my cars for more than a week somewhere other than home, I will buy a jump starter as has been suggested.

My 450h has sat largely undriven on my drive since February. I fire it up once each and let it run for 45 mins during which time it will top and start and stop and start and......all while I am nearby tending the garden or talking with passers by, or reading the Forum. I have on very very few occasions taken it out and about for a short run- no more than 20 miles. It is fine. I have read the Handbook and I understand what it can and cannot do. I have total respect for it.

[paulrnx]

First time my Lexus lets me down by failing to start because of a flat 12v Battery will be the beginning of the end of my relationship with the marque 🙁

I understand what people are saying and I do understand the need to keep a Battery charged up either by driving it, running it on the driveway or trickle charging it. I’m making sure I use mine at least twice a week at the moment but there will be times where it has to be left unused and away from home for longer periods of time.

What would not be acceptable to me is returning to my car to find the Battery is flat just because it hasn’t been run for a week or more. People do go on holiday and park their cars for 2 weeks or longer at a time. I do myself. Can’t think of anything worse than returning to my car with suitcases in tow after a holiday and being unable to start the car.

That said, it hasn’t ever happened to me yet with a Lexus hybrid. Hopefully it never will. My NX is on probation now though - let me down and you’re gone!! 😀

I’m aware that this isn’t just a Lexus issue. More and more manufacturers are packing their cars with systems that require some current and therefore Battery drain whilst the car is off. Hmmnn. Is this progress I wonder? I used to have to keep batteries on charge on the old bangers I used to run many years ago and it’s not something I particularly want to go back to.

[Guest]

45 minutes ago, paulrnx said:

First time my Lexus lets me down by failing to start because of a flat 12v battery will be the beginning of the end of my relationship with the marque 🙁

I understand what people are saying and I do understand the need to keep a battery charged up either by driving it, running it on the driveway or trickle charging it. I’m making sure I use mine at least twice a week at the moment but there will be times where it has to be left unused and away from home for longer periods of time.

What would not be acceptable to me is returning to my car to find the battery is flat just because it hasn’t been run for a week or more. People do go on holiday and park their cars for 2 weeks or longer at a time. I do myself. Can’t think of anything worse than returning to my car with suitcases in tow after a holiday and being unable to start the car.

That said, it hasn’t ever happened to me yet with a Lexus hybrid. Hopefully it never will. My NX is on probation now though - let me down and you’re gone!! 😀

I’m aware that this isn’t just a Lexus issue. More and more manufacturers are packing their cars with systems that require some current and therefore battery drain whilst the car is off. Hmmnn. Is this progress I wonder? I used to have to keep batteries on charge on the old bangers I used to run many years ago and it’s not something I particularly want to go back to.

Fully agree, I have read the manual and can’t find the section that says if going on holiday for 2/3 weeks from an airport don’t forget passport, sunscreen, tickets, back up 12v Battery or portable jump starter!!!!
 

as for the comments about the infotainment being secondary to the cars other attributes, yes it depends on what you want out of a car but I would expect a premium brand to be on a par with its competitors in most areas but on infotainment l don’t think my 2017 Model is competitive, doesn’t mean I don’t like the car but you are allowed to highlight perceived shortcomings 

[paulrnx]

We could perhaps do with some form of poll to see how many people have experienced a flat 12v Battery on their hybrid? It would be good to know if this is an isolated rare occurrence or whether it is more common.

[Herbie]

1 hour ago, Derant said:

Fully agree, I have read the manual and can’t find the section that says if going on holiday for 2/3 weeks from an airport don’t forget passport, sunscreen, tickets, back up 12v battery or portable jump starter!!!!

This is the thing isn't it?

Toy/Lex obviously don't consider it to be a problem or they would either warn us of it in the owners manual or take steps to stop it happening, as we found that Hyundai do on the Ioniq earlier in the topic.

However, and I'm going to say it again, the lack of information or of a practical solution from the manufacturer does not preclude someone from doing their own research (preferably) before or even after buying the car.

I don't recall any mention in the owners manual of having to use ND11 oil instead of PAG oil if the aircon needs to be topped up with refrigerant, but as I mentioned in the list above, if you don't, you could be left thousands of pounds out of pocket. If it happened to you, would you take responsibility for not finding out first or would you go to Lexus and say that it was their fault because they didn't tell you about it?

This is why we have notices on bags of peanuts warning us that this bag may contain nuts!

[ColinBarber]

1 hour ago, Herbie said:

I don't recall any mention in the owners manual of having to use ND11 oil instead of PAG oil if the aircon needs to be topped up with refrigerant, but as I mentioned in the list above, if you don't, you could be left thousands of pounds out of pocket. If it happened to you, would you take responsibility for not finding out first or would you go to Lexus and say that it was their fault because they didn't tell you about it?

Possibly not the best example as servicing of the aircon system isn't deemed an owner's task and therefore wouldn't be in the owners manual. In fact doing it incorrectly in the UK could mean you are breaking the law. For the competent person, they would know to look in the engine bay where there is an information sticker stating ND11 is required on Lexus hybrid vehicles.

[Guest]

42 minutes ago, Herbie said:

This is the thing isn't it?

Toy/Lex obviously don't consider it to be a problem or they would either warn us of it in the owners manual or take steps to stop it happening, as we found that Hyundai do on the Ioniq earlier in the topic.

However, and I'm going to say it again, the lack of information or of a practical solution from the manufacturer does not preclude someone from doing their own research (preferably) before or even after buying the car.

I don't recall any mention in the owners manual of having to use ND11 oil instead of PAG oil if the aircon needs to be topped up with refrigerant, but as I mentioned in the list above, if you don't, you could be left thousands of pounds out of pocket. If it happened to you, would you take responsibility for not finding out first or would you go to Lexus and say that it was their fault because they didn't tell you about it?

This is why we have notices on bags of peanuts warning us that this bag may contain nuts!

Hmmm....how many prospective owners know about ND11 oil instead of PAG oil?

not really may contain nuts is it

[Herbie]

1 hour ago, Derant said:

Hmmm....how many prospective owners know about ND11 oil instead of PAG oil?

not really may contain nuts is it

They would if they researched it, would they not? 

Seriously though, maybe I'm just a one off but when you get something you've never had before, be it a car, a computer, a hifi system or whatever, are you not excited about it and eager to learn all you can about it? I am and that's what LED me to join this owners club in the first place.

[NemesisUK]

2 minutes ago, Herbie said:

Seriously though, maybe I'm just a one off but when you get something you've never had before, be it a car, a computer, a hifi system or whatever, are you not excited about it and eager to learn all you can about it? I am and that's what led me to join this owners club in the first place.

You're not alone. I downloaded and read the owner's manual and Nav manual in the 3 months wait for delivery of my car from Japan. I then joined the owner's club both here and the US version. Soon after I setup an account with Lexus-tech.eu  and read/downloaded loads of tech/service docs for my model. Fascinating stuff!!

 

[royoftherovers]

21 minutes ago, NemesisUK said:

You're not alone. I downloaded and read the owner's manual and Nav manual in the 3 months wait for delivery of my car from Japan. I then joined the owner's club both here and the US version. Soon after I setup an account with Lexus-tech.eu  and read/downloaded loads of tech/service docs for my model. Fascinating stuff!!

 

I`m with Herbie and Nemesis on this. Haven`t we had this sort of discussion many times previously ?