Flat battery issues - IS300H - 2019

[David lings]

I have also over the last week been doing regular checking of my Battery voltage and experimenting with various things.

After a short run (less than 15 miles), or a long run (100 miles plus), the standard state for my Battery is between 12.2 and 12.3 volts.

The car is never stationary for more than 18 hours but the average voltage loss extrapolated to 24hrs is 0.3v.

This suggests leaving the car 3 days without running there would be a serous risk of insufficient Battery power to start the car.

Switching on the hazard lights or ‘power on’ and switch on the radio and the average voltage loss is between 0.3v and 0.4v every 5 mins.

So 15mins and again a possibility of insufficient Battery power to start the car.

This 15 mins is more or less as experienced with ‘auxiliary power’ and the radio.

After around 10mins the radio switched off as did the auxiliary power and a “low battery” warning appeared.

As noted from one response to this topic of Battery life, my IS300h seems very good providing you never use any function without power on  (using the hybrid system).

If I every have to leave the car unused for more than two days and don’t have a jump start facility then I would consider disconnecting the Battery.

Many thanks to all for some useful comments.

David 

 

[iousin009]

51 minutes ago, David lings said:

The car is never stationary for more than 18 hours but the average voltage loss extrapolated to 24hrs is 0.3v.

This suggests leaving the car 3 days without running there would be a serous risk of insufficient battery power to start the car.

This is exactly what I was experiencing. If left for fourth day going completely flat.

[ColinBarber]

18 hours ago, David lings said:

Switching on the hazard lights or ‘power on’ and switch on the radio and the average voltage loss is between 0.3v and 0.4v every 5 mins.

If that is the case, and it suggests you couldn't operate your hazard lights for more than 30 minutes which is a dangerous situation, then your Battery has severely lost some of its capacity, probably by being deep cycled on multiple occasions.

[chef]

On 3/8/2021 at 3:13 PM, wharfhouse said:

If you have been driving the car a few times a week as per the schedule then in my experience the Battery should not be going flat in a few days unless faulty. Now, it could be that the flat Battery incident killed it and whatever test they are doing is not picking that up, but as the car is under warranty I would pursue this with the dealer you purchased the car from - as you bought the car second hand (at a year old) you would have to wonder whether the previous owner (or dealer) has caused the Battery problems, perhaps through it standing around and going flat. Maybe agree to leave the car with them for a few days for them to check after that. Personally I would be a) escalating the issue with the dealer management / Lexus UK or b) ask the dealer to replace the Battery (and pay personally) and then if the problem is resolved push the dealer management for a refund and if no luck escalate with Lexus UK.

The enjoyment of the car should not be spoilt by a 12V Battery and so taking the resolution into your own hands first may be the most expedient way.

 

[chef]

I  bought a 18 month old lexus is 250 16 ooo miles just before covid after 3days idle Battery flat we were with the AA who came out several times to jump start the car back to dealers 3 times said nothing wrong with the car but gave me two new batteris the blame was put on our lack of use. After aweeks hiking holiday the car was dead yet  again the AA cme out again and got us started this time asking if I had fitted the dash cam  i said what dash cam the one near your rear view mirror  I said no must have been the previous owner , he said have it taken out, in his experience an ill fitted dash cam will drain the Battery on a hybrid engine . We did so and no problems since.

[Mr_Groundhog]

I have to say that I'm super happy with a NOCO genius 5 (trickle charger) I bought the other day. Super easy to operate and with programmes for different types of batteries etc. And there are cheaper options too (Genius 1 and 2). Ensures I will never be let down before leaving my garage.

[LenT]

1 hour ago, chef said:

  i said what dash cam the one near your rear view mirror  I said no must have been the previous owner , he said have it taken out, in his experience an ill fitted dash cam will drain the battery on a hybrid engine . We did so and no problems since.

It’s your choice of course, Stephen.  But personal experience tells me that dissing the dash because you blame it for your flat Battery,  is the wrong priority.

The potential benefits of the camera far outweigh the inconvenience of sorting out the Battery problem

Leaving aside the point that it’s a bit surprising that you were unaware of the camera, do you know how it’s currently powered?  If you’re running it off the accessory socket, then it will be switched off with the ignition.  It can then only use any current if it’s operating in standby mode.

This is a very small current and only increases temporarily if the camera is activated by detecting motion. 

If the camera has been connected to a permanently live power supply, then it should have been through a controller that monitors the voltage level to ensure that it doesn’t drop below a preset level.

You don’t say what camera you have, but the one I have for my BlackVue camera is called a Power Magic Pro.

I suggest you consult a competent auto electrician to fit it - and to check if there’s some other fault draining the Battery.  And maybe invest in a CTEK trickle charger

[matt8]

Modern dashcams have a power mode for when the car is off (so you get some recording whilst parked up at the supermarket or whatever) and a drive mode for when the car is on.

There is every possibility it was wired wrongly, so it is in drive mode is set even whilst the car is parked up.

In parking mode, many dashcams offer Battery presentation features so if the 12v Battery drops beneath a predetermined level, it cuts off so the car can still be started.

Seems the dashcam was set up incorrectly!

[Bowserman]

Just made the mistake this morning of sitting with my passenger door open for 25 mins whilst flying my drone. Battery flat and unable to start.

Fortunately I carry a small lithium jump pack and that got me away. Battery currently on trickle charge.

[IS300FSPORT]

Is there not a technique to force start the car when the 12v Battery is low on Lexus models?

I have seen on a Youtube video where a Prius owner claims you can start the car with the traction Battery in emergency circumstances. 

Link below:

 

[Herbie]

That's not guaranteed to work - it purely depends how low the 12V Battery is. If there's enough power to operate the brake pump then it may work if it can recover enough charge but often, it can't.

A better example of what's happening is 'solenoid chatter' in a car with a conventional starter motor. When you turn the key there's enough power in the Battery to pull in the contacts of the starter solenoid and send power to the starter motor, but not enough power to actually spin the motor and crank the engine. Battery voltage falls right down to the point where it can no longer hold the solenoid contacts in and they release, at which point Battery voltage rises and the solenoid is operated again.

The guy in the video is working on the same principle - that there's enough power to operate the brake pump and once the system is up to pressure the pump stops and Battery voltage can climb back up enough to initiate the hybrid start sequence.

[IS300FSPORT]

In the 3 years ownership I have replaced the 12v Battery once when I first purchased the car just as a pre-caution. It is rarely used as its the 2nd car in the family in the 3 years done only 6000 miles. Works out around 2k per annum mainly on long stretches & it has not failed on me yet. The old Battery is now used for doing oil changes on other cars using the 12v oil suction pump. 

Based on the experience of others on this form I decided to Invest in a Noco GB40 - Jump starter as a backup cost £110

(Not had to use it myself yet, however it has helped other people though)

Also every 6-8 weeks or so I fully charge the Battery on the drive using a Noco Genius 5 cost £79. The lowest I have seen the voltage drop to is 12.1v & starts perfectly fine.

To reserve the Battery energy to prevent discharge rate I turn the auto lights off. Also the smart entry is disabled with the key prevents theft. 

In summary if the car is used frequently you should not need to worry about a dying Battery unless of course its past 5-6 year mark this goes with any car really.

The bonus of keeping the 12v Battery fully charged is the car seems to switch to EV mode more quickly &  frequently than normaly when its been sat around 12.1v fully charged seen it around 12.65 volts. 

Expect trouble below 11v

 

 

 

[Mr_Groundhog]

On 2/13/2023 at 11:59 AM, IS300FSPORT said:

In the 3 years ownership I have replaced the 12v battery once when I first purchased the car just as a pre-caution. It is rarely used as its the 2nd car in the family in the 3 years done only 6000 miles. Works out around 2k per annum mainly on long stretches & it has not failed on me yet. The old battery is now used for doing oil changes on other cars using the 12v oil suction pump. 

Based on the experience of others on this form I decided to Invest in a Noco GB40 - Jump starter as a backup cost £110

(Not had to use it myself yet, however it has helped other people though)

Also every 6-8 weeks or so I fully charge the battery on the drive using a Noco Genius 5 cost £79. The lowest I have seen the voltage drop to is 12.1v & starts perfectly fine.

To reserve the battery energy to prevent discharge rate I turn the auto lights off. Also the smart entry is disabled with the key prevents theft. 

In summary if the car is used frequently you should not need to worry about a dying battery unless of course its past 5-6 year mark this goes with any car really.

The bonus of keeping the 12v battery fully charged is the car seems to switch to EV mode more quickly &  frequently than normaly when its been sat around 12.1v fully charged seen it around 12.65 volts. 

Expect trouble below 11v

 

 

 

Could not agree more. I have the NOCO 5 trickle charger and every time im doing stuff in the garden or cleaning the car's interior, I have it charging the Battery in the meantime, as it gives me peace of mind.
What I have found though is that when i first plug it, the NOCO shows me the red light, which seems to suggest the Battery charge drops quite quickly by itself (I was told when I bought the car in Novemeber 22 that Battery had been replaced in May 2022, so not too old)

[IS300FSPORT]

10 hours ago, Mr_Groundhog said:

Could not agree more. I have the NOCO 5 trickle charger and every time im doing stuff in the garden or cleaning the car's interior, I have it charging the battery in the meantime, as it gives me peace of mind.
What I have found though is that when i first plug it, the NOCO shows me the red light, which seems to suggest the battery charge drops quite quickly by itself (I was told when I bought the car in Novemeber 22 that battery had been replaced in May 2022, so not too old)

Interesting do you know if the Battery you have now is AGM or the lead acid Battery? If I'm not mistaken from the factory they came as lead acid & from reading up they dont like a discharge & dont seem to recover well after a deep discharge. The replacement I ordered from Lexus parts direct sent out an AGM Battery, on the Noco 5 charger I haven't seen it glowing red for more than a minute since new the charging cycle usually picks up charge from Amber - Green generally takes 3-4 hours to the solid green light indicating fully charged. It generally sits on 12.1v if the car is left unused for 2-3 weeks straight. AGM Battery dont seem to deteriorate as quick & can handle recharge cycles or recover better.

Owner behaviour plays a massive part like short journeys not giving it enough time to recharge, or leaving the radio on whilst the ignition is off during lunch breaks or when waiting around, Interior lights on & so on.

[Mr_Groundhog]

10 hours ago, IS300FSPORT said:

Interesting do you know if the battery you have now is AGM or the lead acid battery? If I'm not mistaken from the factory they came as lead acid & from reading up they dont like a discharge & dont seem to recover well after a deep discharge. The replacement I ordered from Lexus parts direct sent out an AGM battery, on the Noco 5 charger I haven't seen it glowing red for more than a minute since new the charging cycle usually picks up charge from Amber - Green generally takes 3-4 hours to the solid green light indicating fully charged. It generally sits on 12.1v if the car is left unused for 2-3 weeks straight. AGM battery dont seem to deteriorate as quick & can handle recharge cycles or recover better.

Owner behaviour plays a massive part like short journeys not giving it enough time to recharge, or leaving the radio on whilst the ignition is off during lunch breaks or when waiting around, Interior lights on & so on.

True, but for better or worse (I think better) it is an AGM one. The Mazda dealership guy was decent to get an AGM OEM toyota Battery to replace (if it really is true they changed it, but it does not look old)