Thackeray

This topic came up a few days ago on the IS300h forum. I expect the principles are the same. Here are the comments about it.

I think it's mostly just for fun. In a manual car you might change down to get more power for faster overtaking. You can simulate this for the same reason - higher revs gives more power, perhaps when you're about to overtake. But with this transmission you can get higher revs just by pressing the accelerator in a way that is not possible in a manual. In past years, journalists who didn't understand this described the transmission as being noisy. This is wrong. It's not the transmission that is noisy it's the engine, which like any other engine is noisy if you change down to the lowest available gear when the car is moving at speed. It's just that you can get maximum power in this transmission just by pressing the accelerator, rather than having to manually change down. You can also use the paddles on a long descent of a hill. But I generally use the brakes in order to get maximum power regeneration. If the hill is not too steep you may be able to slow the car enough with a light touch of the brakes which will only use the motor-generators, rather than the brake pads, to feed electricity into the battery. And when the battery is full, the car will increase engine revs automatically to provide engine braking when the battery can take no more electricity. Sometimes you might think the engine is running when in fact no fuel is being used but electricity is being drawn from the battery and the motor-generators are turning the engine without petrol. This is done to reduce the charge in the battery when it's close to the maximum.

My average since 2017 is 42.25 mpg, calculated from one fill-up to the next. I've excluded the covid years when it was averaging mid-20s because I wasn't using the car much. Peak real mpg was around 50-54 mpg, always in August or September for a 300 mile motorway journey. I think the mpg might have benefitted from long motorway 50 mph speed restrictions. Incidentally, I never turn off the air conditioning. Expect to see better mpg as the weather improves. The highest number I've seen on the car computer is 71 mpg after a 20 minute drive starting with a warm engine. I found it hard to believe and the only thing I could think of was that it must have been downhill all the way, even though from the car it looked like flat countryside. I checked on a map and sure enough, although it didn't look like it at the time, there was a gradual decline in altitude for the whole journey. It's a trip I've done more than once and fuel consumption is always much better than usual even though you don't notice the downhill effect while you're driving.

Many thanks for this. After having had the car for so long, it's a surprise to keep discovering new features that I knew nothing about! I'll check this when I'm next in the car. Of course, it might be turned on anway and I've simply never noticed.

I didn't know that. I've never noticed it happening on my car. How can you tell if the station has been switched to FM? Is this something you have to set up in advance and if so do you know how it's done?

Most owners seem to struggle to get the DAB to work. I imagine most just give up and stick to FM. But in case you feel like persisting, I'll add a link to a discussion from three or four years ago. This may or not be helpful as your car may have a newer system. But just in case it helps, here's an explanation of how I got DAB working on my 2014 car.

A long time ago there was a discussion about whether the compression ratio was really 13 to 1. I know Colin Barber explained the setup but as I can't find the thread I'll relate what I remember and hope that someone will correct me if I've got it wrong. The engine uses the Atkinson cycle for improved economy. What this means is that the exhaust stroke is effectively longer than the compression stroke because of the timing of the valves opening and closing. This is aimed at making best use of exploding fuel before it's extracted from the engine. As I remember the discussion, it was concluded that the exhaust stroke is indeed 13 to 1. But the compression stroke after the valves close is actually less than this because of the Atkinson cycle. I got the impression that it's therefore not strictly true to say that it has a compression of 13 to 1, when it's actually the exhaust stroke which is 13 to 1.

I don't think there's anything missing. Mine looks exactly the same.

Maybe an additional factor could be that the Jazz is front wheel drive and the Lexus is rear wheel drive?

One factor to consider in giving up the landline, is how reliable the local mobile phone masts are and how good the mobile reception is at your house. We had repeated problems with reception from local masts, while they were doing upgrade work for several weeks. So, as you may know, the easy solution is to make sure you have Wifi calling available from your mobile phone service provider. This means that if the signal from the local mast is unavailable, the phone automatically switches the call to the internet router in your home. This means you have the convenience of the mobile phone being in your pocket but you also have the reliability of the wired connection to the house. Not 100 percent reliable, of course, but the fibre connection is likely to survive most of the time except for when remote parts of the country are cut off by snow.

It's true to say that you shouldn't attempt to help someone jump start a broken down conventional car from your hybrid Lexus or Toyota. The hybrid 12v electrics aren't designed for the heavy load produced when the conventional car's starter motor draws on the hybrid car's circuitry. Having said that, I seem to remember someone reporting that they had done this without any problems but the possibility of expensive damage is probably too great to take the risk. By contrast, if your hybrid car's 12v battery is flat, you can jump start the car from a conventional car in the usual way. The manual describes how to do this and there's a convenient jump lead connection point under the bonnet so that you don't have to connect directly to the battery. I was once asked to help someone start a conventional car by jump starting from my hybrid Lexus. I said I couldn't do that but I had a cheap Chinese jump start pack we could use. I connected it up and he tried the starter motor. The starter motor didn't turn but the jump start pack started to smoke and looked as if it was about to burst into flame. I decided not to buy another cheap Chinese jump start pack after that experience.

There was a thread a couple of years ago (I can't find it at the moment) where a new owner was reporting something similar. It turned out that this driver was trying to adjust the fans to a preferred setting. But the problem he/she had was that when you adjust the fans, their auto speed setting is also turned off. Everything else remains auto but the fans will continue at high speed if that's how they were set earlier. With climate control set on Auto and the car starting from cold in cold weather, my experience is that there is initially little air coming out of the vents. This is because the air is still cold, even if it's being drawn from inside the car rather than the freezing air outside. But when the engine is warm enough to provide heat (maybe three or four minutes - maybe longer in cold weather) the fans start to speed up to provide warm air to the cabin, including from the face vents. This continues until the cabin has reached the set temperature. The fans then slow down again and the face vents gradually switch to cooler air. So you then have warm air near your feet and cooler air towards your face. But if you make any adjustment, the function you've adjusted will no longer be automatic until you reset the Auto button. I find this works fine. If yours is not doing this when climate control is on Auto and no adjustments have been made manually, then, as you say, there might be a software or sensor problem. Let us know how you get on. Incidentally, here's the link to the earlier discussion, though this was mainly about demisting.

I would have thought 50 miles a day was plenty of driving to keep a healthy battery charged. It's also worth remembering that it isn't necessary to drive the car to charge the battery. It doesn't have an alternator like a conventional car that might produce more electricity if the engine is spinning faster. Instead the 12v battery is charged from the hybrid battery and it only needs to be in the Ready state and the gear selector not in Neutral for the 12v battery to be charged. It makes no difference whether the engine is running or not. I was asking the same sorts of questions around three years ago but I can't now find the thread. When I was asking about the temperature sensor, I think it was Colin Barber who said the temperature sensor is under the battery in the frame (Apologies if I've misremembered this.) So there's nothing to actually connect on this model. But there is a tube for the hydrogen vent that should be reconnected to a new battery, assuming it has a vent. This is to avoid the remote risk of a build-up of hydrogen in the boot area.

Back in the 1930s, brakes on cars weren't very good. They also suffered from "fade", which meant that if you applied the brakes continuously down a long steep hill, there would come a point when they didn't really work any more! (Or so I was told - fortunately I've never experienced this.) So it was pretty important that you didn't use the brakes continuously. Instead, people would change down a gear or two and use the resistance of the engine to slow down the car a bit and give the brakes a chance to recover. The habit continued into the 1960s and 1970s when brake linings were beginning to become a lot more effective and less prone to fade. People have continued to use engine braking down hills even though the original reason for it scarcely exists now. With a Lexus hybrid the situation is different again. When you apply the brakes gently, initially the only braking force comes from the resistance of the motor-generators. Instead of wearing out the brakes, the car generates electricity and stores it in the hybrid battery. Press the brake pedal a bit more firmly and the actual brakes may come into operation as well. But for day to day gentle driving a lot of slowing down can be achieved from the resistance of the generators as they produce some electricity to save in the battery. So to regenerate electricity use the brakes. So what happens when you use the paddles to shift down to a lower gear ratio? As expected, you get some engine braking like on the cars of 80 years ago. But just as 80 years ago this resulted in less brake wear, nowadays in a hybrid it can result in less power being passed to the generator and hence less regeneration, not more.

You probably already know this, but the DAB radio can say No Signal if it's out of range of the selected "Ensemble". When this happens, you have to find an Ensemble which is in range. If the pre-sets are working then the No Signal message might be something to do with this.