Thackeray

That looks very likely. There's a youtube video showing what the test involves and it highlights how short and slow the test is. After looking at the video it's easy to see how a hybrid could spend much of the test running on battery, giving high mpg figures. The same test, which starts with the engine cold, could also give high carbon monoxide emissions. The video shows that some of the test is spent with the car stationary and the engine idling (if it's a conventional car). A hybrid car would probably stop the engine during these stops. As Comedian pointed out above, the catalytic converter needs to be warmed up before it starts removing carbon monoxide from the exhaust gases. But if the engine keeps stopping during the test, the cat won't warm up as quickly as in a conventional car. So the same test, being so short, could show unrealistic figures of both low fuel consumption (high mpg) and high CO emissions. I've now checked and found that Which? has recently updated its test explanation page to describe the new test regime that's due to be introduced soon. It's interesting to see that road testing is going to be introduced to improve the emissions data. I expect that was prompted by the VW saga.

It's true that a lab gives you easier control over variables. But the test is only ever an attempted simulation of real-world conditions. If it's a badly designed test the results will bear no relation to the real world. This is the situation VW got themselves into. They designed cars to do well in the test. But as it turned out the cars did badly when tested on the road. Which? may have done a good job in improving on the design of the official lab test for conventional cars. But it's obvious that their test gives results that are wildly inaccurate for hybrid cars. They say the Prius does 166 mpg around town. I would be very surprised if any taxi driver driving a Prius 10 hours a day could get fuel consumption anywhere near this figure. In real world use, the best fuel consumption of the 2,600 Priuses on spritmonitor.de is 88 mpg. Average is around 54 mpg. The Which? test gets nowhere near to simulating these real world figures. Since the mpg figures are so clearly wrong, I'd be inclined to suspect that emissions data in the simulation will be inaccurate too. I expect they'll come up with a better designed test for hybrids in the future.

For a long time I’ve been puzzled by the Which? magazine review of the IS 300h. In their initial report they made it a Best Buy but a few months later downgraded it. Its website version of the review currently says: “Best Buy award removed. It's a very good car, but we found the Lexus IS emits so much CO (carbon monoxide) in our tests, that it would fail to meet any EU emissions limits set this century. As such, we cannot possibly recommend it.” Despite this negative review, there were lots of things I liked about the car, plus some ratings that sounded impressive: Best in class for 2013 NCAP safety World’s most efficient production petrol engine when launched, at 38.5%. (It was overtaken by a Honda six months later.) Routinely at top of reliability ratings. I was also doubtful about the Which? mpg figures. Their claim of 97 mpg around town was obviously nonsense and the motorway figure of 34 mpg looked doubtful too. They say their tests are performed in a laboratory but they don’t give enough detail to tell how they get to these extreme figures. I thought if the carbon monoxide figures are based on the same testing, they’re just as likely to be wrong. So I went ahead and bought an IS300h. I’ve searched in the past for some other independent CO test reports and couldn’t find any. Until today. But first, what is Which? claiming? They say it wouldn’t meet EU carbon monoxide emission limits set this century. I take this to mean Euro 4 in January 2005. (There was Euro 3 in January 2000 but that was the last year of last century.) The limit for petrol cars under Euro 4 is 1 gram per kilometre (g/km) of CO. So they’re saying the IS300h emits more than 1 g/km. For a long time I had no way of knowing if that was true or not. But at last I’ve found a website that shows real-world emissions test results. It’s called EQUA Index and they test cars by driving them around real roads monitoring the emissions from the exhaust pipe on a three and a half hour run. They give the IS300h their top rating of A++. This represents a band from zero to 0.125 g/km of carbon monoxide. (Their result is for the 2017 model but I don’t think there are any significant differences to the engine from the 2013 model. Please correct me if I’m wrong.) By contrast, Which? says CO emissions are more than eight times this figure. I know nothing about EQUA; I’ve only just come across it. But I’m more inclined to believe that real-world testing on roads will give a more accurate figure than a short test in a laboratory.

Thanks, that probably explains why I haven't seen it. On some other systems, Mercedes for example, they might give you a warning 30 days before the service and then count down the days until it's due.

Thanks for that. Unfortunately, I can't find this section on my car. When I get to vehicle customisation on the central screen I only see options for doors and lights. Nothing for maintenance. When I look at the smaller display behind the steering wheel and choose settings, there is a section for maintenance. But the only option when I select this is Initialisation. I didn't try this as I assume it's what should be done when the car is serviced. I can't find anything about maintenance in my printed SatNav manual either. But I did find another version of the SatNav manual online (called IS+250+-+IS+300h+Navi_OM_53C71E.pdf) Here I can see that there's a section that lists a lot of things that need maintenance: engine oil, oil filter, rotation, tyre, battery, brake pad, wiper, LLC (don't know what that is), brake oil, ATE (?), service, air filter. But I can't get to this page on my car. Any suggestions?

Many thanks. Will a message pop up on the car dashboard to say a service is due? I've been half expecting to see some sort of message but nothing has appeared yet. I've noticed on the 2017 model there's a mileage number next to a spanner symbol as one of the entries as you cycle through the odometer mileages. I assume that means the number of miles to go until a service is due. But I can't see anything like this on my 2014 model. Is there something comparable that I haven't been able to find?

Reviving this old topic, I have a related question. Can anyone help? My car had an intermediate service a year ago, its third service. So it's now due a service in the next week or so. But it's some way off four years old and has a couple of thousand miles to go before it reaches 40,000. Which service is due? Intermediate, normal full service or 40,000?

Many thanks for checking when the indicator cancels on your car. Sounds as though it's just the same as on mine. Thanks for taking the trouble to find out. I'd be interested to hear from owners of other makes of car to see if I'm right in thinking that indicator cancellation works properly on other makes. My guess would be that much of the Lexus development was aimed at the American market, where until recently I believe they had hardly any roundabouts. So no-one would have noticed the indicators cancelling too soon as you went round the roundabout. Maybe the same is true of Japan. If other owners can confirm that this is an oddity unique to Lexus, maybe I could start a new thread to campaign for Toyota/Lexus to fix the problem. I know it's only an irritation but there's no need for the irritation to be there at all. It's just bad design.

You could be right that there's a fault. It would be good to know what other people's cars do. If they're different I'll then know to ask for it to be fixed at the next service.

What happens on most other cars is that if you're indicating right and you turn the wheel from centre to the left (like when you enter a roundabout) it doesn't cancel. You often hear a mechanical click as you turn the wheel past some cog. Then when you actually make the right turn, turning the wheels to the right, the indicator is cancelled when you turn the wheels back from pointing to the right to pointing straight ahead. I can't remember any other car that doesn't do that. What I find irritating is that when I'm indicating right, the indicators are cancelled before I've even turned the wheel a fraction to the right - they cancel when I turn the wheel from straight ahead to the left, which is not the way you want them to work. Obviously, the car computer can tell that I haven't made the right turn yet.

I do, too. It's irritating!

While on the topic of indicators, I wonder if there's any way of getting rid of one of the very few niggles I have about the IS300h. The problem is that the indicators turn off when going round a roundabout before I've completed the manoeuvre. Here's what happens. I'm approaching a roundabout where four roads join. I want to leave at the third exit, effectively turning right. As I approach the roundabout I turn on the right indicator to show I'm going all the way round to the third exit. But as I enter the roundabout and turn the front wheels to the left to enter the roundabout, the indicators cancel. If I want the indicators to continue as I go all the way round the roundabout I have to turn them on again. When I get past the second exit, I switch to the left indicators. But my wheels are now pointing to the right as I drive round the roundabout. If I'm lucky the indicators won't turn off but I have a feeling that in some circumstances, the left indicators are cancelled a second time by the rightward turned front wheels. This is irritating. I don't think I've encountered it on mechanically operated indicator cancellation on other cars. Is there any way it can be adjusted?

It'll be interesting to hear what difference you find if you have climate control set to auto before pressing Demist. Hope it makes a difference. One other point to bear in mind is that the manual says: "Operation of the air conditioning system in Eco drive mode In Eco drive mode, the air conditioning system is controlled as follows to prioritize fuel efficiency: ● Engine speed and compressor operation controlled to restrict heating/cooling capacity ● Fan speed restricted when automatic mode is selected". So, as well as auto climate control, check that the car isn't in Eco mode - ie switch to Normal or Sport - before pressing the Demist button.

Sounds odd that you need to do that. If my climate control is on auto, when I press the demist button the air is directed to the windscreen and the fan speeds up automatically. The windscreen demists quickly. I wonder why your fan doesn't speed up automatically. Is it because you've changed the fan speed from the auto setting? Or is the air conditioning turned off? Or maybe the fan speed only increases when the engine has warmed up a bit. But that seems unlikely from what the RAC website says (mentioned in a link above) as even cold air will help. Another factor of course is that the screen should be clean. In days gone by, before air conditioning, people would wipe the windscreen to get rid of mist. But that just made it worse by putting specks of dust on the windscreen that the mist would stick to. Might be worth checking the air conditioning is working properly.My experience is that the whole car mists up if the air conditioning is turned off in wet or cold weather.

I noticed mine also doesn't seem to be as powerful as on some other cars I've driven. Maybe it's an economy measure. Does the rear screen stay misted if you have the air conditioning on, too?

Over the last few months during the summer weather, my dashboard display showed an average of 50 mpg. The real mpg calculated from petrol bought and miles covered was just over 45 mpg. I'm quite happy with that as it's just above the average for the IS300h of around 44 mpg on spritmonitor.de. (You have to sign in to change the display from litres/100km to mpg.) But since I last filled up, my mpg display since refuelling has plummeted to around 33 mpg (so that's probably around a real 29 mpg). I was wondering why this had happened so looked into it a bit more. First of all, I've been only doing journeys of 4 miles, in stop-start traffic, at an average around 12 mph, in temperatures around freezing. No fast driving at all since refuelling. So I thought I would look at the display that shows fuel consumption minute by minute - I hadn't really looked at it closely before. The interesting thing was that for around the first five minutes of driving the car was doing around 20 mpg. When it was really cold, it might have been for the first seven minutes. Then when the engine had warmed up, it suddenly switched to above 40 mpg and even 60 mpg for some of the minutes. And after less than 20 minutes the journey was over, giving an average for that time of around 33 mpg. I'm not unhappy with that as I can see where the problem lies - I'm driving the car when the engine is cold with headlights, air conditioning, wipers, rear screen demister and heating all turned on . But I'd be interested to hear of other people's experience in cold weather. Is there someone whose typical journey takes them straight from a cold start onto a fast road? In those conditions, how long does it take for the engine to warm up? Is it quicker than the five minutes I'm seeing before the mpg gets back to a more normal range? How does the mpg compare in those first few minutes?

Here's a discussion on battery charge levels. If you scroll down to the post by m.wynn, there's a graphic which I think represents the state of charge for each of the bars on the Prius battery meter. It shows a full range of 40-80% and bar 6 is 55-66%. Whether this is the same on the IS300h, I don't know. I don't actually know how many bars there are on the IS300h battery meter. Does anyone know if it's also eight? My frequent stop-start heavy traffic slow driving usually leaves the car with around three bars when I get back home. In other places, driving at higher speeds often shows a higher reading when the car stops.

My instinct when I first got the car was to want to see the battery meter full. Instinctively I was probably looking at it like the petrol gauge where "full" is reassuring but "low" is worrying (in case you run out). But actually, as a friend pointed out to me, you need the battery not to be full if the car is to make the most of regenerative braking. If the battery is full, any electricity generated from braking is just thrown away. Imagine driving down a long hill with the battery full - all the electricity generated from using the brakes on the downward slope is lost. By contrast, when you're accelerating, if the battery is full, any spare electricity generated from the engine driving the generator (MG1) can be routed to the main motor (MG2), so none of the electricity is lost. So I realised that the best reading for the battery meter is probably around half-full or less, giving plenty of space for generated electricity when you're on a long downward slope. In any case, I've read on a Prius forum that the meter doesn't give an accurate reading of the actual state of the battery. The battery is kept between around 40% and 80% charge. So when the battery meter says empty (I've never seen this) the battery still has a 40% charge; and when it says full the battery has an 80% charge. This is done to extend the working life of the battery as overcharging the battery can shorten its life.

That would be great. The website also lists a number of beeps and bongs that you can control but I wasn't sure if there was one that covered your situation. Presumably it bongs when the door is open plus something else, like the engine is on or the windows are open or something else, rather than just the door open without any other conditions.

Thanks, that's helpful. When I look at the Carista website it shows a list of sample functions that can be customised. This list is different for different makes and models. But it does say they are "sample" customisations, so I was wondering if this was an accurate list or just examples of the kinds of things you could do. For the RC-F it lists dipping mirrors in reverse but if you can't see that as an option on your RC-F then the lists are presumably not accurate but just examples, as they seem to be suggesting.

This sounds interesting. I hadn't heard of Carista before. Looking at its website, it seems to suggest that (among many other features) it would be possible to turn on automatic dipping of the passenger mirror when you go into reverse. Does that seem possible? It's a feature I'd find very useful.

If you haven't got a tin box, you can also turn off the key's wireless transmission. The manual describes this as a battery saving function but as it disables the wireless transmission from the key you also can't open the car doors by holding the door handle. Instead you have to press the unlock button on the key. As far as I understand it, this would make it impossible for a thief to steal the car by amplifying the key's signal - there's no longer any signal to amplify. To disable the key, hold the lock button down while you double-press the unlock button. The red light on the key will flash four times to confirm the wireless transmission is turned off. You can also check this has worked by attempting to open the car by holding a door handle. The doors won't open when the key is turned off.

Interesting point. I'd often wondered if the car journalists who criticise the transmission were usually drivers of manual gearbox cars and weren't very familiar with driving automatics. I've had automatics for decades and didn't find much difference in the IS300h, except that the CVT is smoother. I've always found that driving an automatic needs a slightly different approach compared with manual gearboxes. With a manual, you're constantly doing a dance between the clutch and the accelerator, a lot of the time pressing one while releasing the other and vice versa. Double declutching requires even more pressing and releasing of both pedals. But my approach to driving automatics, including the IS300h, (and maybe I'm not typical) is first to press the accelerator to a point that gives me the acceleration I want. And then I keep the accelerator still as the gearbox shifts through the gears until I've reached the speed I want. Then I ease off on the accelerator to a point that will maintain the speed I want and then I keep it still again until I need to speed up or slow down. If you expect a lot of pressing and releasing of the accelerator like on a manual box, the results may be less than ideal. With years of operating with this habit, driving the IS300h was no different. The only difference was that there was no sound of gearchanges and no lurching as the car shifted through the gears. ( I noticed earlier in the year how odd it looked as I was pulling away from lights alongside cars in the adjacent lane. Whereas the IS300h maintained a steady rate of acceleration, the cars alongside would edge ahead and then drop back as they changed gear; then edge ahead and then drop back; and so on. I decided I preferred the smooth approach without the gearchange jolting.)

I don't think sheep have the required acceleration for this market segment.

You had me puzzled for a while! I think I've worked it out now, though. Is it ring-gear? By the way, the transmission version is identified on the VIN sticker on the door pillar. The IS300h has the L210, which I think is the rear-wheel drive version of the front-wheel drive P410. I might be wrong but I think the GS300h also has the L210 transmission, as does the RC300h. One of my favourite features of the power-split device is that when cruising at 50 mph, the engine is turning at around 1200-1500 rpm. At 70 mph it's still doing 1200-1500 rpm; even at 80 (cruising at 130 kph on French motorways) it's still doing 1200-1500 rpm. This helps to make the car so quiet, even at motorway speeds. My first automatic car did 3000 rpm at 70mph; the next did 2600 rpm, and my previous automatic did 2400 rpm at 70 mph. With this transmission, the engine is turning at half the rate at cruising speeds. I think this is a really great feature.