12v Battery Potential Problem

wivenhoe · March 11

The 12v Battery in my car went flat and the doors wouldn’t open even with the mechanical key. AA gained access and jump started the car.

I have not driven the car for almost 3 weeks so my wife started and ran the car every couple of days for 20 mins.

My tracker monitors the 12v Battery in case it is disconnect it by thieves. It warned me that even having run the car for 20 mins 3 days earlier the 12v warning was amber as the voltage had dropped to 11.8v. I therefore asked the dealer what the resolution was and could they do it in the first service. Their response was (as Toyota also say)

Your Battery will start to drain when the vehicle is not driven for a period of time. A new Battery will not stop it from happening again in the future.

We would advise having a solar charger supplied. We can supply one for £50.00 inc. It plugs into your diagnostic port under your dashboard and will help maintain your Battery when the vehicle is not driven.

I pointed out that most airport car parks are multi storey so what Lexus were saying is that I will have to call the AA after 2 weeks holiday (probably waiting outside of car) for them to jump start.

I cannot believe that they well know of the issue and suggest the only resolution is to use a solar charger for £ 50 !

Thought with Easter coming owners should know before flying off.

Malc1 · March 11

Wot a bluddy nonsense all this with more modern cars …….. why put oneself thru’ purgatory and such inconvenience when a more conventional car would suit much more sensibly ……, brill old fashioned Ls400 technology surpasses all this !

Malc

wivenhoe · March 11

Agreed !

Notamech · March 11

It is an unfortunate reality with hybrids / electric cars. The 12v Battery is a small one only meant to boot the computer and power the security systems when locked. Maybe keep a jumpstart pack in your boot. Theyre essentially like a powerbank which you connect to your Battery and can jump start it yourself if you get stuck. Maybe learn how to access the car if the Battery dies. Calling the AA everytime will be very inconvenient.

Malc1 · March 11

Inconvenience in just not being able to get in the car, start and GO ……. like an ordinary simple tech old fashioned petrol car …… this is bonkers paying a small fortune for a dreadful way of motoring ……. EVs will be obsolete before too long carrying on like this ……. who on earth could wish for one ☝️

Malc

Bob, sorry to go on like this ……. It infuriates me that you’ve been conned into this mode of transport …….. my heartfelt sympathies

M

ColinBarber · March 11

3 hours ago, Malc1 said:

EVs will be obsolete before too long carrying on like this

It's a problem with all modern cars, especially hybrids and EVs.

Some EVs (Tesla and some Kia/Hyundai for example) will auto wake and charge the Battery itself if it detects it going flat.

ColinBarber · March 11

5 hours ago, wivenhoe said:

I cannot believe that they well know of the issue and suggest the only resolution is to use a solar charger for £ 50 !

Yes that is a poor response. If it is that known an issue then they should be supplying them with the vehicle - anyone who can afford a new Lexus EV is likely to take 2 week holidays! Plus a solar charger would have been completely useless during the last 3 months.

wivenhoe · March 11

Thanks for the sympathy ! I found it ridiculous that a ‘prestige’ manufacturer would say the resolution to a defect is to faff about with a heath robinson solar charger, which in any case won’t work in the majority of long term car parks. Oh and buy the way we £ 50 for you resolving our defect.
We will have to pay in 2 years time when free AA cover ends as the Battery is not covered by the extended warranty.
I also learned today that if you leave the car connected for a few days that will flatten the Battery even quicker.
There isn’t anything in the manual about having to run the car every couple of days !
Toyota have known about this for years before the RZ was marketed but did nothing about it. During lockdown they issued a guidance saying to start the hybrids and run the car in Ready Mode for 60 mins at least once a week - https://mag.toyota.co.uk/coronavirus-toyota-hybrid-car-maintenance/?utm_source=ToyotaOwnersClub&utm_medium=ForumLinks

wivenhoe · May 8

My car was in for its first service today and I collected the solar charger. I've put it under the floor in the boot, hopefully hardly to be used.

It was noticeable that they removed the RZ from the showroom and replaced it with a NX, such is the demand of a new RZ.

I changed the tyres to Michelin Cross Climates about 4k ago and the video review confirmed that they and the brakes "were like new" so lugging the very heavy Battery around doesn't seem to increase.

DavidCM · May 8

On 3/11/2024 at 8:09 PM, ColinBarber said:

Yes that is a poor response. If it is that known an issue then they should be supplying them with the vehicle - anyone who can afford a new Lexus EV is likely to take 2 week holidays! Plus a solar charger would have been completely useless during the last 3 months.

Whatever happened to starting handles?