Flat battery issues - IS300H - 2019

[iousin009]

Hi Members,

As most of the peeps have experienced similar issues mentined in this thread

I'm also on the same boat. I have a 2019 IS 300H, bought from Lexus in September 2020. For two months it was fine, but soon when weather started getting colder, the Battery kept getting flat.

First it happend when the car was driven for 1 mile in two weeks, still not acceptable. I drive my 2006 Mazda 6 once a week and didn't had the issue.

Had to call AA, he jump started it and advised to drive/start for at least 30 minutes every week. Lexus recommendation is 60 minutes every week. I have been driving 30 minutes one every 3 days and then at least 1 hour on the 6th/7th day. Even after this if I leave the car for 4th day the Battery gets flat.

I've tried the Halfords 2.4 solar charger alog with the OBD 2 cable, it didn't help.

My problem is the car is parked on the road and I can't run main cable to use a noco 5 genus charger. So now looking at getting a portable power station that I can keep in the boot while the noco is plugged in to the Battery. Hope it goes well and there won't be any alarm when the power station is running and the car is closed.

Have been a big far of lexus having previously owned IS 250, never had such issue, the Hybrid was a bad choice, it doesn't suit my driving style and now I have to live with it....

[wharfhouse]

11 minutes ago, iousin009 said:

Hi Members,

As most of the peeps have experienced similar issues mentined in this thread

I'm also on the same boat. I have a 2019 IS 300H, bought from Lexus in September 2020. For two months it was fine, but soon when weather started getting colder, the battery kept getting flat.

First it happend when the car was driven for 1 mile in two weeks, still not acceptable. I drive my 2006 Mazda 6 once a week and didn't had the issue.

Had to call AA, he jump started it and advised to drive/start for at least 30 minutes every week. Lexus recommendation is 60 minutes every week. I have been driving 30 minutes one every 3 days and then at least 1 hour on the 6th/7th day. Even after this if I leave the car for 4th day the battery gets flat.

I've tried the Halfords 2.4 solar charger alog with the OBD 2 cable, it didn't help.

My problem is the car is parked on the road and I can't run main cable to use a noco 5 genus charger. So now looking at getting a portable power station that I can keep in the boot while the noco is plugged in to the battery. Hope it goes well and there won't be any alarm when the power station is running and the car is closed.

Have been a big far of lexus having previously owned IS 250, never had such issue, the Hybrid was a bad choice, it doesn't suit my driving style and now I have to live with it....

I'm not sure why quite a lot of people have 12V Battery problems with the IS 300h (and other hybrids), especially on such recent cars. My 2014 IS 300h with 96K miles is still on it's original Battery and I have never had an issue starting the car. Admittedly it doesn't get left for months without being driven, but it is often left for a week, sometimes a bit more, without driving it - longest time was for 2 weeks a couple of years ago - in fact the last time it was left a week was in late January this year in sub-zero temperatures for most of that week and it still started without any issue. I do keep one of the Li-Ion Battery starter packs in the car just in case (seems a small price to pay for something so useful, especially as the Lexus hybrid only needs the computers booting) and although I haven't had a need to use it yet I would recommend anyone to get one, just need to charge it a few times a year and keep it on hand. In the past on our non-hybrid cars, including BMWs, Hondas and Fords (all bought new or nearly new), the 12V batteries all lasted around 8 years (pretty much independent of car brand and mileage - some cars were doing around 20K miles a year and some 6K miles a year).

As I understand it with any 12V car Battery, once they have gone flat the chances are that the life is shortened - though I have had batteries flattened once or twice in the past (like leaving lights on by mistake) and they seem to have lasted as long as others. Certainly the first time any of our cars didn't start the Battery was then replaced (didn't bother trying to squeeze any more life out of it or take  a chance with it failing again) and all was fine going forwards, but as I said none of these replacements were unexpected with the batteries being 8 years old or more. I expect that my current Lexus Battery will fail me in within the next couple of years, so I will make use of the Li-Ion Battery pack to start the car, replace the 12V Battery like for like and not worry for probably as long as I keep the car... 

If the 12V batteries are failing on cars that are a few years old after being left for a few days then it sounds like there is another problem with perhaps a Battery drain or the Battery has previously been flattened before, maybe more than once, damaging it (maybe on a 2nd hand car sat at the dealers?) and if so then replacing with a new Battery, then using the car regularly, and keeping one of the Li-Ion packs on hand should alleviate any concerns.

[iousin009]

This car had been jump started 5 times until now, three times by AA/RAC then 2 times by myself using Noco jumpstart.

To make the situation worse, when the car doesn't start the alarm also goes off and all the neighbours as working from home peep out and see me trying to start the car. It's so embarassing, the price I have to pay for Luxury!

Even after recent testing (on 25th Feb) Lexus servicing are keen that the Battery has no issues. I'm not sure what to do, have been to two diferent service centres now, both the time they have been tested and just recharged the Battery and adivsed that, this is a common issue nowadays due to lockdown, just try driving more!

It's good to know that older models (even hybrids) don't suffer with this problem, this makes me think the electrics of newer models have been added without proper thought.

[Bounce75]

I am afraid I would push the Main dealer more on this issue, you should not have to be paying for a new Battery on such a new car!!

[Brechin Slate]

5 minutes ago, iousin009 said:

this makes me think the electrics of newer models have been added without proper thought.

Hi Ahmed

Can of worms opened yet again..  It does sound like there's a drain on your Battery.  If you're driving it and it still goes flat then there's a problem.  Have you tried the Lexus recommended method of leaving the car in Ready mode for an hour?  The engine will start and stop during that time and it's best if you have nothing drawing power like A/C, radio, lights etc.  If you've done all this and your Battery is going flat within a few days then there's a bigger issue to be investigated.

[wharfhouse]

1 minute ago, iousin009 said:

This car had been jump started 5 times until now, three times by AA/RAC then 2 times by myself using Noco jumpstart.

To make the situation worse, when the car doesn't start the alarm also goes off and all the neighbours as working from home peep out and see me trying to start the car. It's so embarassing, the price I have to pay for Luxury!

Even after recent testing (on 25th Feb) Lexus servicing are keen that the battery has no issues. I'm not sure what to do, have been to two diferent service centres now, both the time they have been tested and just recharged the battery and adivsed that, this is a common issue nowadays due to lockdown, just try driving more!

It's good to know that older models (even hybrids) don't suffer with this problem, this makes me think the electrics of newer models have been added without proper thought.

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.

[iousin009]

53 minutes ago, Brechin Slate said:

Hi Ahmed

Can of worms opened yet again..  It does sound like there's a drain on your battery.  If you're driving it and it still goes flat then there's a problem.  Have you tried the Lexus recommended method of leaving the car in Ready mode for an hour?  The engine will start and stop during that time and it's best if you have nothing drawing power like A/C, radio, lights etc.  If you've done all this and your battery is going flat within a few days then there's a bigger issue to be investigated.

Hi Brechin,

Thanks, have not tried this exactly, will give it a go. Right now too afraid to leave it off without driven for more than 3 days.

[iousin009]

52 minutes ago, 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.

Thanks. The car was bought directly from dealer and as per him it was company used car and not had any such issues. I will get in touch with them again and try to push for a Battery replacement. Will this usually be a Battery problem or something is running in the background while the car is locked? For the latter, I tried discussing them once, the receptionist mentioned for any investigation there will be £300 charge (this will be refunded if any issue is found and under warranty). Do Lexus charge this for investigation for the cars under warrany? Maybe she was trying to discourage me not to go ahead with the investigation.

Will ask them for a Battery replacement first, even if I have to pay, then can approach for a refund, will be sensible approach.

The car has become a pain rather than an enjoyment for me 🙂

[wharfhouse]

1 hour ago, iousin009 said:

Thanks. The car was bought directly from dealer and as per him it was company used car and not had any such issues. I will get in touch with them again and try to push for a battery replacement. Will this usually be a battery problem or something is running in the background while the car is locked? For the latter, I tried discussing them once, the receptionist mentioned for any investigation there will be £300 charge (this will be refunded if any issue is found and under warranty). Do Lexus charge this for investigation for the cars under warrany? Maybe she was trying to discourage me not to go ahead with the investigation.

Will ask them for a battery replacement first, even if I have to pay, then can approach for a refund, will be sensible approach.

The car has become a pain rather than an enjoyment for me 🙂

I think that the dealers can/do say there is a charge for investigation but if they find a fault you don't pay anything (if they don't then you pay for the investigation) - at least that's how it worked with my Extended Warranty (they found a fault so I never paid anything) but never had anything done under the initial manufacturers warranty to see if they have the same approach. If you go with the option to pay for the Battery then keep (or get) any paperwork where Lexus said that the Battery was OK on investigation (especially as you had this twice) to follow up with them if the problem is then resolved.

[Brechin Slate]

1 hour ago, iousin009 said:

The car has become a pain rather than an enjoyment for me

Pretty sure that once this issue is sorted to your satisfaction you'll enjoy the car once again.  Remember that it's one of the most reliable cars on the market and Lexus has an enviable reputation for customer service which you might want to mention they'll be anxious to keep 😉 

[iousin009]

30 minutes ago, Brechin Slate said:

Pretty sure that once this issue is sorted to your satisfaction you'll enjoy the car once again.  Remember that it's one of the most reliable cars on the market and Lexus has an enviable reputation for customer service which you might want to mention they'll be anxious to keep 😉 

Cheers Mike. 🙂

[200h]

if your going to be charged £300 for an investigation it maybe better to

spend that money buying a new Battery instead.

[200h]

5 hours ago, iousin009 said:

I've tried the Halfords 2.4 solar charger alog with the OBD 2 cable, it didn't help.
 

dont expect miracles with a tiny solar panel

on my previous house i had 17 solar panels on my roof ( nearly 4kw's)

during the winter months i could create 60 wattts of power from them

so i doubt the solar panel from Halfords would make any noticable difference to

the state of charge in your Battery, i've also heard that when using

a solar panel you should use a solar controller otherwise during darkness

the solar panel can take power from the Battery and start to drain it.

if your using an OBD2 adapter again dont leave it plugged in all of the time

as this will drain power from the 12v Battery and help to flatten it.

[iousin009]

4 minutes ago, 200h said:

if your using an OBD2 adapter again dont leave it plugged in all of the time

as this will drain power from the 12v battery and help to flatten it.

Yes, this solar charger was pretty useless have removed it now. Waiting for my power station to arrive to check if the noco charger will help. Have also got a Battery tester will keep eye on the Battery charge, on Sunday before doing my weekend run (1.5 hours, 45 mins up and down) have used the tester, the Battery was at low (red indicator). Then after coming back it came to medium charge (yellow). Will test again tomorrow and see and start recording the actual voltage.

[Herbie]

What actual voltage do you get at the Battery terminals (a) when the car is open but NOT in ACC or READY mode, and (b) when car is in READY mode?

The chart below will show (a) and (b) should be about 14.5V:

[matt8]

15 hours ago, iousin009 said:

for any investigation there will be £300 charge (this will be refunded if any issue is found and under warranty)

Seems a bit unfair.

Your job is to present the problem / symptoms.

Whether they can find it or not I'd argue is irrelevant. What if there was an inexperienced technician looking at your vehicle that day and they couldn't find it due to their own shortcomings? That's not your problem.

Your Battery tester will help here. Take a voltage reading and log it. Run the car for the 1 hour as per manual. Take another reading each day. If within a week it's flat and you can't start the the car again, you can tell the dealer you followed the manual and you've got a record of the Battery voltage each day. With such evidence, they can't argue there isn't a problem, and you've followed the instructions perfectly.

Then leave it with them to investigate and sort!

[200h]

i am sure in the hidden service menu (press & hold menu button then lights on & off 3 times)

there is a voltage reading , if you use this voltage reading they cant argue that the

reading is in accurate as they could with your own meter.

[iousin009]

17 hours ago, Herbie said:

What actual voltage do you get at the battery terminals (a) when the car is open but NOT in ACC or READY mode, and (b) when car is in READY mode?

The chart below will show (a) and (b) should be about 14.5V:

Done today after approximately parked for about 44 hours (just less than 2 days). Following are the readings. The 11.X think we can ignore as can be tester fault.

Before Start - 11.95 -> Gosh, thought it was flat, but when tried to start it started fine, phew... Coule be testers fault as just opened the bonnet and put it.
After Start - 14.05 -> Is this something to worry about? Although the device is saying Good alternator.
After Stop - 12.36

 

Will do same again tomorrow.

Images attached.

[iousin009]

6 hours ago, 200h said:

i am sure in the hidden service menu (press & hold menu button then lights on & off 3 times)

there is a voltage reading , if you use this voltage reading they cant argue that the

reading is in accurate as they could with your own meter.

I'll try this, how to reach the hidden service menu?

[iousin009]

6 hours ago, matt8 said:

Seems a bit unfair.

Your job is to present the problem / symptoms.

Yea the £300 for investigation was off putting. Looked like they are so confident that don't expect any problem or just trying to avoid any timewasters. But why people will bother them unless facing some issue. Have got the tester and do the readings, lets see.

[Thackeray]

56 minutes ago, iousin009 said:

Before Start - 11.95 -> Gosh, thought it was flat, but when tried to start it started fine, phew... Coule be testers fault as just opened the bonnet and put it.
After Start - 14.05 -> Is this something to worry about? Although the device is saying Good alternator.

The lowest I've seen (and someone else reported this in another thread) is that it will successfully get into Ready state from 11.4v. I suspect it will go even lower but I haven't heard of any reported cases.

While the car is in Ready state the charging voltage from the DC/DC inverter will vary depending on the temperature of the Battery and possibly the state of charge of the 12v Battery. When the car first starts up I've seen around 13.9v initially, rising to around 14.4v as the car warms up.

[iousin009]

3 minutes ago, Thackeray said:

The lowest I've seen (and someone else reported this in another thread) is that it will successfully get into Ready state from 11.4v. I suspect it will go even lower but I haven't heard of any reported cases.

While the car is in Ready state the charging voltage from the DC/DC inverter will vary depending on the temperature of the battery and possibly the state of charge of the 12v battery. When the car first starts up I've seen around 13.7v initially, rising to around 14.2-14.4 as the car warms up.

Hi William,

So the 11.95 could be the actual voltage? After starting the car I stopped it after a minute or so and it came down to 12.36, which one will be my current Battery voltage? Do another test again after few hours without starting?

[Thackeray]

I expect it could be 11.95 unless you have reasons to distrust the meter. It will rise quite quickly while in Ready state but an hour or so after turning the car off I doubt it will still be at 12.36. More likely 12.2-12.3. And tomorrow, lower again.

The 14.5 figure isn't the Battery voltage. It's the voltage of the charging current coming from the hybrid Battery via the converter/inverter. As soon as you turn off the car the 12v Battery will be showing the lower figure again.

[Herbie]

Remember, at this stage we know the Battery has been flattened a few times so it may be damaged and not able to accept as much charge as it used to.

For accurate measurements you really need to take the Battery into the house and put it on charge for about 12 hours or at least overnight so that (a) we know that electricity is only going into the Battery and nothing can be draining it or lessening the charge it's getting, and (b) this will give us a known baseline voltage to work with and we'll know it's the best that can be achieved.

[iousin009]

27 minutes ago, Thackeray said:

I expect it could be 11.95 unless you have reasons to distrust the meter. It will rise quite quickly while in Ready state but an hour or so after turning the car off I doubt it will still be at 12.36. More likely 12.2-12.3. And tomorrow, lower again.

The 14.5 figure isn't the battery voltage. It's the voltage of the charging current coming from the hybrid battery via the converter/inverter. As soon as you turn off the car the 12v battery will be showing the lower figure again.

2 days before when I parked and recorded it was yellow don't remember the actual voltage but think would have been 12.3x, is it normal to go down to 11.95 in 2 days, or something is running (that shouldn't run) and draining the Battery?

I've got my power station delivered, will use the noco charger tonight. Then will start monitoring the Battery depletion.