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I do not understand why such a car has such a Battery failure, if left standing for a week or two, or in my case in a hospital car park with the radio on for 40 minutes. RAC called and sorted. Battery tested by RAC and good. The least should be a warning on dash OR maybe an sms or email from the cars system. 1300 pages of manual and no comment, I can find. Odd at best. This is not explainable or needing owners to obtain a solar charger. It is a design fault. 

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Hi Phil and welcome to the LOC.

It sounds like you have already discovered from previous posting the Battery appears to be the weak point on the hybrids, some members have taken to using smart chargers if power is available or as you mention solar chargers.

I totally agree that this should not become an issue but with the reduced physical size of the Battery and it’s capacity it is unfortunately.

With all electric vehicles now being pushed and the power network already near full capacity I can see the breakdown services getting rather busy especially if someone decided it would be fun to disconnect your car from the charging cable on the way back from the pub. Or even worse someone trips over your charging cable with our ever present blame and claim culture.

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29 minutes ago, PCE said:

It is a design fault. 

Not a design fault, more a lack of use as designed or lack of maintenance?

Have a read of the attached Lexus-tech.eu  document. It includes Lexus' recommendations on 12v Battery maintenance 

Maintenance of hybrid battery.pdf

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Yes not a design fault in as much as it works as designed but is poor design because there are accounts from all over the world where people have left cars at airports for example and returned in 2-3 weeks time to find they have a flat Battery.  More cars were affected  due to non use during pandemic.  I even got an email from Lexus warning about Battery needing to be topped up.  Judged by industry standard this compares poorly with other marques.  Also agree about need to recharge 12v Battery from traction Battery if you want radio on for more than 20 mins.  The 12v Battery is just too small!

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Echoing much of the above it is not a design fault and works reliably if the car is used in a regular way. My IS 300h is 7 years old and has now done 111,000 miles on the original 12V Battery. The car has been left on occasions for a week or two (even recently and in sub zero temperatures) with no issues starting again. I do however use the car regularly. The lockdowns seem to have caused a lot of the issues with 12V batteries as they have been discharging too low on a regular basis and then not had the longer time in use to properly recharge again. Smaller capacity batteries are not a new thing - we had a 2004 Honda Accord Tourer with a similar size Battery to the IS 300h and that was a normal ICE. There were complaints back in the day that car had a design fault for the Battery being too small but again we had no issues with regular use (the Battery lasted as long as any other before needing replacement) other than my wife flattening it one evening leaving lights on and listening to the radio whilst waiting to pick someone up. Lesson learnt. With the IS 300h if you are waiting in the car and listening to the radio etc just leave the car running and you have all the power of the hybrid Battery available to keep everything running, the car will stay warm or cold depending on what you want through the climate control, and if the hybrid Battery starts to go down the car will simply start up the ICE to recharge everything. 

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4 minutes ago, wharfhouse said:

With the IS 300h if you are waiting in the car and listening to the radio etc just leave the car running and you have all the power of the hybrid battery available to keep everything running, the car will stay warm or cold depending on what you want through the climate control, and if the hybrid battery starts to go down the car will simply start up the ICE to recharge everything. 

That's the beauty of the hybrid over normal ICE cars. My Mercedes had a Rest function that, with the engine off, it would keep the heater going to keep the car warm. BUT it wouldn't cool the car and even in winter wouldn't dehumidify the recirculated air resulting in badly steamed up windows (ok they cleared very quickly once the engine was started) and the radio would shut down after a short period of time.

I can sit for absolutely ages (wife 'just popped' into shops!) in the RC300h car in the Ready state and in Park. The hybrid Battery lasts and lasts and eventually the ICE kicks in and recharges it in a matter of moments. 👍

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It is a design fault in that it's small and could/should have been bigger.

It isn't a design fault in that it works as designed.

I don't think Phil's comparison to a 2004 Honda is relevant because there would be far less electrical equipment in that.

The real, main 'problem' is that Lexus don't tell us about it. It should be in the owners manual, prominently displayed so that we all know in advance and we know what we have to do. As the old saying goes, "Knowledge is power" - in this case, quite literally. However, I can see why they don't as some people would start ranting that this is just not good enough for a luxury brand and not what should be expected of cars costing £40k or more.

The good thing is that it's a relatively minor problem, doesn't cost a fortune to fix, and once you know what's happened and why, you can plan for it and shouldn't be caught out again.

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47 minutes ago, Herbie said:

I don't think Phil's comparison to a 2004 Honda is relevant because there would be far less electrical equipment in that

My 2004 Honda Accord Tourer (a top spec trim) had pretty much the same equipment levels as my 2014 IS 300h Executive level trim. Both cars had/have small 12V batteries (the Honda one was physically about two-thirds the size of what one normally associates with a 12V battery). However both cars deliver(ed) as designed IMHO and with normal Battery care (regularly runs of a decent length) both have performed to my expectations and yet both have had their fair share of criticism. Could they both have larger capacity batteries - possibly - would a lot of the problems have still existed - probably - especially with recent lockdown and people driving just a few thousand miles a year instead of the (as designed) mileages of 10,000 miles plus a year.

Interestingly with my other cars I used to see many complaints of components failing that I never experienced. The common factor always seemed to be cars that were coverted and did very low mileage. In my experience cars deliver the least issues when running regular 10K+ per annum mileages and especially a reasonable amount of long runs in that (rather than short runs of a few miles now and again). When I bought my IS 300h it was two years old but with 40K miles on it. That was actually something I was quite pleased about as I knew it had been used regularly and mostly motorway use. It also made a lot of financial sense as many people would have shyed away from it so I was able to negotiate a good price. 

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6 hours ago, PCE said:

battery failure, if left standing for a week or two, or in my case in a hospital car park with the radio on for 40 minutes.

I know a lot of people have claimed that the radio will run the 12v Battery down very rapidly but I'd be interested to see any evidence that this is so. I'm doubtful that the radio on its own would need a lot of power to operate.

Last summer, with time to kill waiting to pick someone up, I checked the impact of the radio on the voltage of the Battery, with the car on the ACC setting rather than Ready or IGN. It started off at 12.5v, went down to 12.4v when I turned the radio on but went back to 12.5v when the radio was automatically turned off after 20 minutes. Here's a link to that thread. I doubt that the effect would have been much different when I turned the radio back on for a further 20 minutes - it always turns off after 20 minutes in ACC mode.

If the Battery dies after 40 minutes of radio use, my guess would be that the battery's charge was already very low when the radio was turned on. It might also be that the car was on the IGN setting (two presses of the power button) rather than the ACC setting (one press of the power button). The IGN setting activates a number of other features in addition to the radio so the power usage would be higher but I haven't checked the impact on the battery's voltage to compare with the ACC setting.

 

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Mmm. Loyal Lexus owners who say.  Not design fault as it works as designed, but it is poor design. 

Own up it is a design fault. Just sort it for the next "design" release. 

I had 8 jaguars over many years and never called break down. 

Just lucky I guess.  I averaged 50k in each of them

Happy new year. I sign off now.

 

 

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Initially confused by the acronym “ICE” which I had always understood to mean “In Car Entertainment” and given that it was also mentioned that the problem on several occasions occurred after the radio had been left on. I did however deduce that the same now relates to Internal Combustion Engine.

I think aviation is the ultimate environment for acronyms, anyone know the following without getting google involved ...PAPI, ATIS, ECAM and TOGA ( the last example not being a Roman garment) 😀

Answers on post 12,005.

 

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On 12/26/2021 at 9:32 AM, NemesisUK said:

It is a design fault. 

On the UX owners platform there is an owner of an UX300e all electric that ironically has 12v Battery issues if car has been left standing for a few days ....who'd have thought that eh!

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Must say I find it unsatisfactory to rely on drivers doing 10K per year.  There are many reasons why it could be used  far less, such as second car for occasional use by partner, used to get truck driver to his vehicle where he then drives abroad for long journeys before returning and for many other reasons. I've heard of sales people extoling the fact that car will do mega miles pa but never that you should do 10K min pa, notwithstanding the fact that it's not good to leave it for months on end without some use.

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3 minutes ago, Barry14UK said:

Must say I find it unsatisfactory to rely on drivers doing 10K per year.  There are many reasons why it could be used  far less, such as second car for occasional use by partner, used to get truck driver to his vehicle where he then drives abroad for long journeys before returning and for many other reasons. I've heard of sales people extoling the fact that car will do mega miles pa but never that you should do 10K min pa, notwithstanding the fact that it's not good to leave it for months on end without some use.

But all equipment has to be designed to a sensible operational envelope and to a price within that envelope and for cars that is probably around 10k miles per annum as an "average" mileage for most people. Of course there will be extremes of high and low from this but then it's not unreasonable to have users take additional precautions such as for very low mileage cars ensuring the 12V Battery has some extra maintenance care. My car does around 15k miles per annum but our second car does only 5k miles (or less per annum) and so I take some additional precautions with that car to ensure we don't have issues. In reading various car forums it's invariably the very low mileage cars that seem to have the most problems and not the average (or even high) mileage cars. 

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4 hours ago, Duggie B said:

On the UX owners platform there is an owner of an UX300e all electric that ironically has 12v battery issues if car has been left standing for a few days ....who'd have thought that eh!

Not sure you are quoting the correct person?

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Indeed a rather odd oversight on a £40K car not to be able to run the computer software more intelligently. I put a power meter on my 300h and it seems to require 4Watts per hour when doing nothing. The max Battery capacity is 12Volts x 60Ahrs = 720watts i.e. it should be able to hold out for about 720W/(24hrs*4W) = 7.5 days. Which isn't great. Not only that you can't get the total power out of a Battery so that would be an over estimate. I'm sure somebody out there might be able to confirm or correct.

My solution, looking at the various suggestions on this forum, is to use one of the small Lithium batterys, they cost about £60 and have it trickle charge/run the software. It has about 6Amp Hours at 12V =72 hours approx. The advantage is you can grab the Lithium Battery, it indicates its charge level, and recharge it in your house in an hour or so, then pop it back on. If you can't charge the car's 12V Battery using a trickle charger, no driveway or mains point, this seems an easier solution. After testing this as a way I'm going to do a minor mod to the Boot 12V Battery cover panel so I can tidily get at the cables. At the moment I have removed the plastic grab handle (4 screws) and this allows me to feed the connector through can keep the panel on. It isn't ideal but if I keep it simple Mrs Wife will hopefully not be too of put. Really they should offer us a mod to jump power the 12V Battery from the main power change batteries.

The other method, using photocell chargers could work but you would need to be able to charge at 8Amps to 12Amps +, especially with our short winter days, in order to keep it topped up.

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4 hours ago, Barry14UK said:

Must say I find it unsatisfactory to rely on drivers doing 10K per year.  There are many reasons why it could be used  far less, such as second car for occasional use by partner, used to get truck driver to his vehicle where he then drives abroad for long journeys before returning and for many other reasons. I've heard of sales people extoling the fact that car will do mega miles pa but never that you should do 10K min pa, notwithstanding the fact that it's not good to leave it for months on end without some use.

Many marques will recommend maintenance schedules for low mileage cars. The likes of Mercedes will recommend one purchases a trickle charger (at a vastly inflated price over the unbranded version) for their £100k+ cars because they know they will only be driven  infrequently.

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5 minutes ago, WillOz said:

Indeed a rather odd oversight on a £40K car not to be able to run the computer software more intelligently. I put a power meter on my 300h and it seems to require 4Watts per hour when doing nothing. The max battery capacity is 12Volts x 60Ahrs = 720watts i.e. it should be able to hold out for about 720W/(24hrs*4W) = 7.5 days. Which isn't great. Not only that you can't get the total power out of a battery so that would be an over estimate. I'm sure somebody out there might be able to confirm or correct.

I have left my RC300h for up to 21 days without any sign of problem.

When you measured the Battery drain did you allow the car to fully go to sleep? It can take a significant number of minutes. Also the entry/exit system shuts down to sleep mode after ~10days that basically stops the car listening for the key fob signal. When parked up the 12v Battery is only powering the entry system and the alarm

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On 12/26/2021 at 9:32 AM, NemesisUK said:

Not a design fault, more a lack of use as designed or lack of maintenance?

Have a read of the attached Lexus-tech.eu  document. It includes Lexus' recommendations on 12v battery maintenance 

Maintenance of hybrid battery.pdf 408.77 kB · 18 downloads

It is a design fault. It is a bit like having a laptop that when you don't use it goes flat in a few days but worse there is still a lot of electrical energy in the car you can't use. Not everyone has access to trickle charging and running the petrol engine isn't really the best environmentally it seems to me. I take your  point that going by the book might seem like a solution but my 2019 300h has gone through two 12V batteries from Lexus and doesn't last more than 5 days. Lexus says it is because I have all the bells and whistles electronically but it does seem a bit rum. 

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Well all I can say is that in order to put a power meter on you have to disconnect the Battery to put the shunt in, I assume that will make it take a nap, but perhaps not. Running with 6Ahr subsidiary Battery that shows its charging level, it was drained in about 3 days so 4Watts per hour seems to make sense. It is a pity there is no car system method of seeing 12V Battery levels indeed it could then go into deep sleep mode but still have enough power to start. I do love the car I was just caught out with my first week, when Lexus swapped it out for a new one, and later on when even with moderate mileage 5 days non use seems to flatten it. I suspect it isn't the actual mileage but how often it is used. But I'll stand  correcting on that. One thing I did notice, on a frosty morning, when the windscreen was frozen, the area around the camera was defrosted so it must be using power, for what reason I no not. Perhaps if I take that off things might improve? Any thoughts?

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52 minutes ago, WillOz said:

It is a design fault. It is a bit like having a laptop that when you don't use it goes flat in a few days but worse there is still a lot of electrical energy in the car you can't use. Not everyone has access to trickle charging and running the petrol engine isn't really the best environmentally it seems to me. I take your  point that going by the book might seem like a solution but my 2019 300h has gone through two 12V batteries from Lexus and doesn't last more than 5 days. Lexus says it is because I have all the bells and whistles electronically but it does seem a bit rum. 

I suggest that your car does not appear to be working as designed in that case. The 12V Battery will last at least 5 days if it has been properly used previous to that. If it has been depleted before being left then of course it may not last 5 days. To have a brand new Battery fitted and if using the car regularly and still not able to leave it 5 days then there is something not right causing a drain. I only speak from experience of my 7 year old (110k mile) original fit Battery that will still be fine after 5+ days left standing. My wife's 2+ year old Toyota Yaris hybrid has just started quite happily after standing for 2 weeks and that has much the same tech as Lexus. 

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Thanks Wharfhouse. I am new to hybrids so all info is good many thanks for your time. However when I quizzed the sales people and after sales rep he did say they had an increasing number of this 12V Battery problem. It all does seem to depend on what level of kit you have using the electronics. I can't see why anything would be running apart from the key and security system. Oddly I bought this ex demo nine months ago and it was the After Sales reps car! However all they could suggest was charging and testing the Battery. It has just been serviced so again I'm surprised it wasn't picked up, the computers log everything, well not really but...

The After Sales Rep did point out that all the cars in the show room were on trickle charge.

Anyone any idea what the wattage drawdown should be or indeed what should be drawing this power?

Cheers and thanks for all the ideas.

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