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Of the car, that is.

Does anyone have any observations on Battery maintenance during lockdown? We know that we can keep the 12v Battery in good nick indefinitely by using a smart charger.

But what about the traction Battery? How long can it safely be left idle?

I suspect there might be a lot of flat batteries of one sort and another around when we are all released!

And any other simple tips to keep the car up to scratch during this longish lay-up?

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Hi John.
The HV Battery should be good for quite a considerable period. I bought a gen2 Prius in an auction that had not run for 3 years.
After sorting out some electrical problems with the AC system causing a ground fault on the high voltage system, and replacing the 12 volt Battery the car started up immediately with no further actions. The HV Battery still had a charge level of three blue bars.

If you know the car is not going to be used, and will not go to "ready mode" for an extended period before parking the car up make sure there is as much charge as possible in the HV Battery. This can be safely done by going to ready mode, and "D" and with your left foot firmly on the brake apply the accelerator with your right foot until the desired charge level is reached. This will not harm the transmission. It just uses all the engine energy to force charge the Battery.

John. 

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The traction Battery should be good for a couple of months but my first thought is that you'll need to go food shopping won't you? Unless you live very close to a supermarket then you could make a trip there and that should be enough.

Otherwise, maybe once a week I'd go and sit in the car with the system in the READY state for about half an hour. The system itself will fire up the engine and sort things out, just as it would do if, say, you were parked up on the prom watching the sea and listening to the radio.

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Thanks guys - useful info.

I won't comment on my personal situation, enough to say that the question occurred to me yesterday. I don't use the Lexus for food shopping - it doesn't risk supermarket car parks - my wife's Seat Mii is for that. And what if we have more stringent restrictions - you thought that couldn't happen here...could it?...but hinted at this morning.

My nephew was recalled to his battalion two weeks early a few days ago.....

There will be an end to this mess and you'll want your car to be in good shape then

Another few tips if your car is going to be laid up for the duration - keep the 12v Battery charged - it will discharge within a month or so if left parked with the alarm set. If you can't hook it up to a smart charger in the car consider pulling it out. If you haven't got one, a smart charger (eg Cetek or CSI Airflow - others are available) might be a good investment. If you have an AGM Battery it will not like complete discharge (neither will a flooded Battery really) and it may well be permanently damaged or compromised so that you may need to buy a new one - that'll cost more than a charger.

If you do remove the 12v Battery you will have no alarm - but no-one is going to drive your car away with no Battery. You could consider pulling some vital fuses and/or relays but make a note of where they go!

Consider putting an extra 10psi in the tyres to mitigate flat spotting.

Protect the interior if the car will be out in the open - cover the dash with cardboard and the seats with covers of some sort - it's surprising how much a car's interior can deteriorate with time in the sun.

I prefer a full fuel tank during storage - I lay my MX-5 up for six months every winter - looks like it will be well longer this year. The fuel may well deteriorate to some extent, but a large amount with no air will go off much less than a small amount in a tank with a lot of air. It has never caused problems for me.

More ideas welcome!

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if your concerned about the hybrid Battery going flat you could pull the hybrid Battery fuse

to prevent anything draining it,with regards to your 12v Battery as long as you have another

12v Battery even something like this house alarm backup Battery

https://www.toolstation.com/sealed-lead-acid-battery/p79562

will get you started in the event of it being flat, dont forget you are only powering up the computers

and once powered up the hybrid Battery takes over for everything else.

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The hybrid Battery is

8 hours ago, 200h said:

if your concerned about the hybrid battery going flat you could pull the hybrid battery fuse

to prevent anything draining it,with regards to your 12v battery as long as you have another

12v battery even something like this house alarm backup battery

https://www.toolstation.com/sealed-lead-acid-battery/p79562

will get you started in the event of it being flat, dont forget you are only powering up the computers

and once powered up the hybrid battery takes over for everything else.

The hybrid Battery is totally isolated when the car is not in ready mode by two high voltage relays. one in each supply line. Pulling the HV isolator fuse plug will not help. It is self discharge that is the problem, but this discharge rate is very small on the hybrid Battery.

John.

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On 3/28/2020 at 5:12 PM, Britprius said:

This can be safely done by going to ready mode, and "D" and with your left foot firmly on the brake apply the accelerator with your right foot until the desired charge level is reached.

Hadn't thought of doing this. Does it make a difference being in Drive rather than Park? If the engine is running, doesn't it charge the hybrid Battery while it's in Park as well?

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15 minutes ago, Thackeray said:

If the engine is running, doesn't it charge the hybrid battery while it's in Park as well?

Yes, it does. We live about 40 minutes from a sea front and if we go there during rainy weather we'll sit in the car with the radio on, the transmission in 'P' and the engine fires up as and when necessary.

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I believe the only mode  in which the traction Battery doesn't get charged is 'N' (neutral)

I was also under the impression the accelerator is 'disabled' when the brake pedal is depressed?

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9 minutes ago, NemesisUK said:

I was also under the impression the accelerator is 'disabled' when the brake pedal is depressed?

It may work differently on different models. On the IS I have the impression that in Normal mode the accelerator is disabled in Park whether you have your foot on the brake or not. That's to say, you can't rev the engine while the car is stationary in Park. But just a couple of days ago I discovered that you can rev the engine in Park when you select Sport mode. Not really my area of expertise, but I imagine this is important for people who like racing the adjacent car away from the lights and you need to blip the engine menacingly while the lights are still red.

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The accelerator does work in drive with your foot on the brake, but it has to be pushed further than normal to get the engine to start and then run at medium revs. It does not increase the revs if more accelerator is applied.
When in this mode the outer ring of the planetary gear is held still along with MG2. With the engine running it then forces MG1 to spin at speed generating electricity to charge the HV Battery. All the Toyota/Lexus hybrids operate in this manor.
If you use "P" the engine will charge the Battery to a low level then turn off once the engine is warm. It will then restart if the HV Battery gets lower on charge or the engine cools below a given level. The charge rate in this mode is slow because the engine is at it's tick over speed, and does not generate much electricity. It will also not top the Battery up to the full bar level, but usually to the 3 or 4 bar level.

John.  

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Interesting replies to this question, as it was something I was wondering about.  When I had the Civic Hybrid, there was a label under the bonnet saying

"This car must be used for at least 30 minutes every month."   I suppose a quick drive at least once a fortnight would be OK ? ( without getting out ).

Although if stopped by the police they might take a dim view..   Before the forum police  anything, yes I realize what an essential journey is.

 

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3 hours ago, Hadrian said:

Interesting replies to this question, as it was something I was wondering about.  When I had the Civic Hybrid, there was a label under the bonnet saying

"This car must be used for at least 30 minutes every month."   I suppose a quick drive at least once a fortnight would be OK ? ( without getting out ).

Although if stopped by the police they might take a dim view..   Before the forum police  anything, yes I realize what an essential journey is.

 

Because of the way the Toyota/Lexus hybrid works it is not necessary to drive or move the car.  Not having a Honda hybrid I do not know, but with these it is possible it must be driven to charge the hybrid Battery.

John. 

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Understood John, but it's always good to use a car at least once a fortnight. Even if for only going a couple of miles.

 

Alan

 

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I've always believed that if one only uses a car infrequently one must ensure that when it is driven everything gets up to full working temperatures. That should also include the exhaust, making sure to drive out and dry out condensation, otherwise one could be accelerating corrosion in the exhaust.

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Just thought I'd chime in - my GS450h was parked in a garage for 12 months untouched. It was connected to a wall charger to keep the (then) factory 12V Battery topped up. As it entered hibernation, it was 10 years old, had done 105k miles, had half tank fuel, tyres at 40psi all round, and hybrid Battery showed 4 blue bars. I just parked it up and didn't lock it with the fob.

When I got back to it a year later, the factory 12V Battery had depleted anyways and tyres had lost between 10-15psi each. After a new 12V Battery, it started right away and hybrid Battery still showed 4 blue bars  🙂

Rear tyres had flat-spotted (Michelin Pilot Super Sports with 3mm left), but the fronts were perfect (Pirelli something, newer pair with ~7mm). Aircon gasses had escaped (yet the system passed the pressure test prior to regassing - strange). Also never needed regassing in the 2 years that it was running thereafter.

The car has just been SORN'd again and parked up in the garage as above, but as I'll remain in the country and home-bound this time, I plan to keep the tyres topped up for a change  🙂

 

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5 hours ago, Hadrian said:

Understood John, but it's always good to use a car at least once a fortnight. Even if for only going a couple of miles.

 

Alan

 

Yes I agree Alan, but in the situation we find ourselves in, and for people that have SORNed there cars for the duration to save a considerable sum of money this is not possible. I hope not, but our cars could be off the road for as long as 6 months.
I am in the fortunate position that I can not only charge the 12 volt Battery, but also have the equipment, and knowledge to charge the traction Battery. This requires a 350 volt DC current limited supply for the GS450H, and the ability to run the Battery cooling fan without using the cars system to do this.

Fortunately for most people long periods of standing idle is not a problem for the HV Battery. The 12 volt Battery is a different ball game particularly when it is a few years old. I changed my 12 v Battery from a 70AH to a 110 AH Battery last summer, and put the details in a post here on LOC. This means it should be ok for 3 months or more, but for the longevity of the Battery I have it on permanent charge from my caravan Battery charging system as the car is parked next to it. The caravan Battery stays on charge 24/7 when the van is out of use. Even when only partly discharged a lead acid Battery will sulphate up in a short period of time

John.

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3 hours ago, LexIS200Sport said:

Just thought I'd chime in - my GS450h was parked in a garage for 12 months untouched. It was connected to a wall charger to keep the (then) factory 12V battery topped up. As it entered hibernation, it was 10 years old, had done 105k miles, had half tank fuel, tyres at 40psi all round, and hybrid battery showed 4 blue bars. I just parked it up and didn't lock it with the fob.

When I got back to it a year later, the factory 12V battery had depleted anyways and tyres had lost between 10-15psi each. After a new 12V battery, it started right away and hybrid battery still showed 4 blue bars  🙂

Rear tyres had flat-spotted (Michelin Pilot Super Sports with 3mm left), but the fronts were perfect (Pirelli something, newer pair with ~7mm). Aircon gasses had escaped (yet the system passed the pressure test prior to regassing - strange). Also never needed regassing in the 2 years that it was running thereafter.

The car has just been SORN'd again and parked up in the garage as above, but as I'll remain in the country and home-bound this time, I plan to keep the tyres topped up for a change  🙂

 

Ganesh.
As reported in an earlier post you found the same as I did that even after very long periods the hybrid Battery does not suffer from high internal discharge rates, and so maintains it's charge very well.

John.

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Hi all..

This is sort of an observation and a question.. my GS450h has been parked up for nearly 2 weeks now, and the keyless entry has become erratic.  I can't open or start the car first thing in the morning, then 20 minutes later it's fine.

I measured the 12v battery at 12.35v after sitting all night.. is this low enough to mess with the keyless entry?

Thanks 🙂

 

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I would have thought that was enough voltage from the car Battery.

What about the fob Battery? Are you keeping the fob in your pocket and it's getting warm between attempts?

Maybe that is boosting the fob signal?

Sent from my PSP7551DUO using Tapatalk

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..thanks John.

The batteries in both fobs measure 3V, though I've ordered some new ones. That's a good point about the the heat in my pocket.. I thought maybe the 12v Battery was heating up enough in the morning sun to bring it above some threshold 🙂

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It is the case for both key fobs?

 

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I have found that when the fob Battery gets below 3.1 volts the fobs operation becomes erratic. Sometimes I have to hold the key near the door instead of leaving it in my pocket. I have also come across the situation where I have had to hold the fob by the start button before the car accepts that the fob is there. 

John.

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..yes, both fobs.

So I suppose the first thing to try is the fob batteries, so I'll report back when they turn up. For the moment I can lock/unlock the car with the physical key, and start by touching the fob on the start button, though it's funny how tense you feel waiting for some sort of "can't detect key" message to appear just as you stab the go pedal down a clear on-ramp 🙂

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..fingers crossed, but the new fob Battery seems to have done the trick.

The old Battery measured 3.04V, and the new one 3.40V, so yeah it looks like anything below 3.1V could be sketchy alright. It's probably worth keeping a fresh CR1632 handy as they don't seem to stock them on every street corner.

Thanks 🙂

 

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