Thackeray

So if the car has done 180,000 miles, I make that around a penny a mile for the hybrid battery, if in fact it turns out that you have to replace the whole battery and not just one cell. That's about the same as I reckon for tyres, which generally also cost me around a penny a mile. For someone who's keeping the car for the long term or doing high mileage that doesn't sound too bad. It only becomes more of a risk for someone who buys an older car with 200,000 miles on the clock for, say, £5,000, and is then hit with the whole cost of the battery. It would be great to hear some more updates on how the problem is fixed. Do you need to replace the whole battery or is it just one cell bringing up the error message? There are stories of Prius taxis doing 200,000 or 300,000 miles on the original battery but the IS300h may not produce the same life for the battery.

I'd second that. I checked my car after around six days of being unused and was surprised to find the 12v battery was down to 11.47 volts. The car still started ok and I ran it for an hour to charge up the battery. I then realised I had left the Carista adapter plugged in for the week. I think that must be the reason for the battery drain. Usually the battery reads around 12 volts after a week without use. I must try to remember to unplug the Carista adapter when leaving the car unused for a while!

I seem to remember you said you were trying Hybrid Assistant a couple of months ago. If you've got any of the records from then you could compare what the percentage state of charge was then and whether it's changed now. The bars on the meter don't represent the full capacity of the battery. The lowest my battery will go is 40% (generally shown as two bars or very occasionally as one bar) and then the engine starts. The engine then keeps running until the battery has reached 50% (three bars) and then it stops. In normal use, the battery percentage is generally in the 50s (three to five bars). I believe the maximum it will go to is 80% at which point motor-generater 1 (MG1) will start drawing power from the battery to reduce the charge. If the car is stationary MG1 will be spinning the engine as a load to use up the excess power and it sounds as if the engine is running but in fact it isn't using any petrol while being spun by MG1. If there has been a change in the software, I wonder if they have simply changed the number of bars used to represent any given percentage. This might be because people instinctively think it's good to have more bars rather than fewer, as you would with the petrol tank. But the battery is more like a container that you're using to collect excess energy. If it's already full you can't collect any excess energy. So ideally you would want the battery to be around 50% capacity. That would give plenty of room to save energy from braking but also enough already stored for a quick burst of acceleration.

I wondered about this, too, before I bought my car. It sounds like an expensive repair if you have to pay for it yourself. I did wonder if I should choose a different car because of this potential cost. But my thinking then was that if you hit something at over 16 mph you'll almost certainly be claiming insurance anyway. And if the bonnet pops up at parking speed (it's not supposed to activate below 16 mph) that would be very annoying but maybe Lexus could be persuaded there was a fault and pay for repair if an insurance company said there was no damage to the bodywork. But ultimately, what persuaded me was the thought that if some pedestrian stepped out in front of me without looking (it's a quiet car) and died of head injuries after hitting the bonnet and the hard metal of the engine below it, this would not be annoying like an extra cost or an insurance claim, this would be devastating. I know some people could shrug this off but I don't think I could. The pop-up struts are designed to place a gap between the soft aluminium bonnet and the hard metal bits of engine below so that head injuries are more survivable. If I knew that this device could have saved a life and it had been disabled, I think this would be even more upsetting. A cost of £3,000 (even if I had to pay it myself) would be insignificant by comparison. So I decided to go ahead buying the car and I haven't regretted it yet. No sign of the bonnet popping up yet, either.

Probably an unnecessary question but is the window completely clean - dust and grease free? And do you keep the air conditioning on? It will mist up if the air conditioning is off in winter weather and the window hasn't been cleaned for a while.

Yes, the bit in the article that caught my attention was the paragraph that said, "Since Adobe will prevent Flash Player from displaying content from 12 January, there are concerns that years of animations, games and interactive websites will be lost." Quite how Adobe achieves that I don't know, unless Flash code has had an end date built in for a long time. But it's useful to read that people are working on emulators to replace it.

Just to clarify, this is the 12 volt battery not the hybrid battery. I thought I'd corrected this when I posted the message but the clarification seems to have disappeared!

There are a few more days left to see the best graphic showing how the Toyota/Lexus hybrid transmission works before it disappears from the internet. This is the graphic that I found the most useful in understanding the system and for anyone who hasn't seen it, I'd recommend a last look before it's gone. The graphic was created in Adobe Flash but this is being withdrawn and apparently will stop working in mid-January. The page has two graphics - one at the top and a more elaborate one at the bottom. The one at the bottom has sliders that allow you to adjust the speed of the cog wheels and see how this affects the other interconnected cog wheels. To see the one at the bottom of the page, you will probably have to click to allow Adobe Flash to run. It works on Windows but I don't think it works on an Android phone. This is the page where you can still find it for the moment: http://eahart.com/prius/psd/ I've read that Adobe Flash can be converted into html5 format using Adobe Animate so maybe there's someone out there who has the expertise to preserve this graphic in a new format before it disappears. Otherwise, I'd recommend a last look if you haven't seen it before.

I had some drips of water coming in from above the battery. Finally tracked it down to the rear window seal. Although this isn't directly above the battery I think drips must have been running down some inside bodywork strut and finally falling down above the battery. Sealed it with silicone sealant. That probably isn't what you're seeing as you had moisture around the boot lock. But it might be worth a check if you can't find the leak elsewhere.

A possible problem is that one of the sensors has stopped transmitting. Either its battery is flat or it's broken. Before spending lots of money at a dealership, as 200h says above you can find out which sensor is faulty by using a Carista OBD plugin adapter. There are more sophisticated and more expensive OBD adapters but the Carista is fine for checking tyre sensors. I think they offer a free trial of their app. But if not I use a free app called Tire Assistant with the Carista adapter. Tire Assistant tells me the pressure reported by each TPMS sensor, its ID number and the tyre temperature. If you see that one of the TPMS sensors is not reporting a pressure you'll know that this is what's turning the warning light on. You'll then have to work out which sensor is in which tyre by adjusting pressures and checking which sensor shows the changed pressure. Here's a thread about Tire Assistant:

Just out of interest, when you disconnected the other battery and the one in the car was showing 11.2 volts, were you able to start the car (or get it to the Ready state) with just 11.2 volts? I've often wondered how low the voltage can go and still be enough to start the car.

The vacuum wipers were great! If you accelerated when it was raining the wipers would slow down. If you accelerated hard the wipers would stop!

Three-year-olds hot-wire a BMW https://www.youtube.com/watch?v=6SIFwULdnPw

For the last few months I've been using an app called Tire Assistant which displays the readings transmitted by the TPMS sensors. I've found that the sensors are pretty accurate when checked against a reliable pressure gauge. Garage pump gauges are often inaccurate. This is a link to a thread about Tire Assistant. When the car is starting from cold the engine runs at a low power setting for about a minute and it doesn't generate any electricity that can be saved in the hybrid battery during this low power state. I've read that some Prius drivers try to maximise their mpg by not driving the car until this low power state ends. This is interesting but probably not worth doing in financial terms. But if I'm not in a hurry I sometimes start the car and then check Tire Assistant while the engine warms up for a minute or so before setting off. I don't have to get out of the car to check the tyres and with little effort I have the reassurance before setting off that the tyres are ok.

Interesting to read this as the hybrid transmission does not have any gears or clutches to engage like a conventional automatic. The clunk could be the release of the parking pawl if the car has edged forward after Park was engaged. But an Audi automatic will be the same as this (Is the Audi automatic?) Since nothing else is happening when you engage Drive, could it be that Lexus has gone to the trouble of creating an artificial clunk to make the car feel more like a conventional automatic? It's hard to know what else it could be as nothing mechanical actually happens when you engage Drive except for the parking pawl and some changes in the electrical circuits. When stopping, you could try engaging the parking brake before you release the footbrake and before you engage Park. Then the parking pawl in the transmission won't be holding the car on any incline. If it still clunks when you engage Drive it sounds as if it might be an artificial noise to give the feel of a conventional car.

It won't make any difference to speed of charging because, as you say, the 12v battery is charged from the hybrid battery. This happens at the same rate whether the engine is running or not. The only difference is that going for a spin will use more petrol because the engine will need to run more often.

I was going to say that but you beat me to it! The system is waiting for the engine coolant temperature to reach a useful level that can actually heat the cabin. So paradoxically it can mean that on a really cold day when the engine is at zero degrees or lower the fan won't start up for a longer period (even though you need the heat sooner!) than on a mild day when the engine starts at 10 or 15 degrees. I'm not sure how long this might be but I have the impression that it could be as much as five minutes on a cold day. At least it's not a diesel where you might have to wait 10 minutes for any heat to start to come through. While you're waiting the heated seats can help.

That doesn't sound right. Does it still do this when the cabin has warmed up? Mine is pretty quiet most of the time. I keep it on auto most of the time and around 21 or 22 degrees. There's a big contrast in fan speed if I turn on the windscreen demister, which does set the fan to full speed.

If a Tesla costs, say, £60,000 and it depreciates 45% in the first three years, that's about £9,000 per year. Somebody must be paying for this and I suspect it's the owner.

This is what the manual for the IS300h says I thought I remembered it said something about the "whooshing". I didn't remember the warnings about static electricity, so that's useful to be reminded. Now I just need to work out where there's some unpainted metal.

You are so right. There was a time (many decades ago) when software writers would write the user documentation and for an intelligent user it read like a foreign language. When the documentation is done, it needs to be tested on intelligent users who have never encountered the system before (detailed previous knowledge means the test may not be valid). A document test manager needs to monitor how the user follows the document, makes false steps, gets stuck when a vital step is not spelt out etc. Then the document can be changed to account for these mis-steps. The problem can be that the software designer may just excuse the documentation by implying that the user is stupid. This is wrong. If the user can't get the product working from the documentation, then the documentation needs to be fixed! In the project plan, there needs to be a task headed Document Testing! If there isn't, the documentation is unlikely to be as good as it could be. (I hope you can tell your project manager to put this heading in!)

What do you test? The thing that irritates me is that a lot of big companies don't bother with Document Testing. So they issue user manuals that users can't understand. It's a pity after all the work that has gone into producing their product that they don't understand it's vital to explain to the buyer how all the functions work. Same thing applies if you're only producing products for internal use - the accompanying user guides need to be tested to make sure people can understand them.

Herbie will spot this shortly and can give you a detailed explanation. But in case you're in a hurry, I'll just summarise what he has said in a number of other threads. Electrically, it makes no difference whether you put the black lead on the battery negative (sometimes called earth) terminal or anywhere on the car body or chassis. This is because the battery's negative terminal is connected to the car chassis to provide the return route for the electricity rather than having a separate wire to serve this purpose. The reason it's recommended not to attach the black lead to the battery itself is because there might be hydrogen gas lurking around the battery and a spark as you make the connection could cause an explosion. If you connect to some bare metal bit of the car, any spark would be further away from any gas near the battery. If you have a sealed battery it's pretty unlikely that there will be any hydrogen and sealed batteries like the AGM type used on many of the Lexus hybrids have a vent to route any hydrogen away from the battery. Herbie has said in his many years of working with electrical systems he has never heard of an actual explosion. When connecting jump leads, the recommended order of connection is red (positive) first and black (negative) second. I assume this applies to chargers too. When disconnecting, it's the reverse order. Disconnect black first, then disconnect red. Again, I think this is to avoid sparks.

Try Lexus Parts Direct. They're generally very helpful if you phone or email to confirm the battery for your car. The following might be what you need, currently £112 for an IS300h. https://lexuspartsdirect.co.uk/parts/lexus-is/lexus-is-phase-iii-2013-present/lexus-is-3-engine-service-kits/lexus-is-phase-3-12v-starter-battery/ They also have a Black Friday offer of free delivery at the moment. Your profile says you have an RCF. The battery for this is £79. Part number 28800-YZZZH

The power to the windows stays on for about 30 seconds after the car is turned off. So if you've forgotten to close the windows before turning off the car, you've still got around 30 seconds to do it without turning the car back on.