Thackeray

You could start the car with one of these mini jump start devices like this The prices seem to have gone up recently - perhaps lots of people are buying them because of flat batteries. Previously they were available for £20-30. I don't know this particular brand but there are a several of this kind of device available. Once you've started the car, it will charge normally. Or if you don't run it for very long you can trickle charge the battery later with a separate charger.

That's a great description - I must remember it! I know exactly what you mean. In the clip I posted above, I don't particularly like the intro with the piano bass strings damped with a hand inside the piano. I think what makes the clip above challenging to listen to is not the guitar, piano and bass, all of which are fairly straightforwardly melodic; instead, it's the complexity of the drums. I have the imression that we understand music because we instinctively understand (a) the harmonic relationships of the notes, (b) we understand the structure of a tune (eg 12 bar blues) and (c) we understand rhythm (eg 4/4, waltz, even something a little more complex like bossa nova or reggae). The problem with this piece is that - even though the harmonics and the structure are pretty orthodox (apart from the intro) - it's hard to judge what the rhythm is. Eventually, it clearly resolves into a straightforward 4/4 - it might as well be a march. But it's the confusion in your brain leading up to this that makes it either annoying or intriguing, depending on how you react. I probably like it for the same reason I like the elegance of the Lexus hybrid transmission - the complexity that is derived from such a simple design and the challenge of trying to understand how it works. So come on those of you who are musicians, Listen to it again, don't bother with the tune or the structure which couldn't be simpler, but tell me what Manu Katché is doing on the hi-hat? And Etta James is, of course, a great choice - right up there with "At Last", which I notice on just one version on youtube has 42 million views, so plenty of people agree she was great. So for those who don't like any kind of jazz, how about electro-swing? Here's a band that was influenced by Django Reinhardt, who apparently also inspired Martin Taylor posted above by Bluesman. Watch out in the video for the prettiest French car of the 1960s.

And now for something completely different... Scanning through the selections above, i've found some of them are ones I already have in my car or already know well: The Eagles, Bruce Hornsby, John Mayall, Eric Clapton. Of the styles of music, there's rock, pop, easy listening, folk, 12-bar blues; but i haven't yet spotted any jazz. So here's something a bit different. For the musicians among you, can anyone tell me what Manu Katché is doing on the drums? He seems to manage to be playing triplets (is this right?) on the hi-hat for the entire piece, while playing the off-beat of a 4/4 rhythm on a drum rim from around 30 seconds in. I don't know how he can sustain this mismatch of rhythms for so long!

I would guess you're right, though I don't know for certain. I don't think it would cause excess wear on the brakes as the car wouldn't be moving but it might cause wear to the electric motors, though maybe someone can correct me on this. In a conventional automatic, the car does keep pushing when you have the footbrake on and the car is stationary. These hybrid cars simulate this because lots of people are used to it. But I'm pretty sure that when the hybrid car is stationary and you have your foot on the footbrake the car is using no energy and is not trying to move forward. It edges forward when you take your foot off the brake because this is what conventional cars do, and they've designed this one so it seems the same. There's no reason why it should begin to move when you take your foot off the brake - it's just that this is what most people expect if they're used to conventional automatics. I suspect the parking brake is not the same. For example, if you leave the parking brake on when you put the car in Drive and you press the accelerator, the car will start to move but you'll hear loud beeping and a flashing light on the dashboard to show the parking brake should be released. The parking brake might hold the car stationary but I don't know if the car is attempting to move as it would be on a conventional car. On a related topic, you may already know that you don't need to use the parking brake to do a hill start. If you stop on a hill and hold the car with the foot brake, the car won't start to roll back for about 3-4 seconds after you release the brake to give you time to start pressing the accelerator to move forward. Incidentally, my air conditioning creaks too when the car starts up. I always assumed it was just making initial adjustments after registering current temperature and so on. I never attempted to have anything done about it.

Don't put it into neutral at traffic lights - you'll be running down the hybrid battery while you're in neutral instead of charging it, especially if you have air conditioning etc turned on. At worst, if you kept doing this, it might not start up again from the lights - though I expect you'd see plenty of warning messages before it reached this low level of battery charge. If you don't like keeping your foot on the brake you could put it in Park and ignore what the person behind thinks. But there's no wear involved in staying in Drive with your foot on the brake and that's how they're designed to be used, as are all conventional automatics. Just because you're used to putting a manual gearbox into neutral at the lights doesn't mean you need to do that on this kind of car!

As the video shows, there's a fair bit of play in the parking ring - the slots are quite far apart compared with the grooves of the cog wheels. So the lever may have to slide into one of the slots, creating a bit of movement and the shifter may wobble, depending on whether the lever drops straight into a slot or not. This is normal on all automatic cars. But it seems like a good idea to release the footbrake gently so that it doesn't jolt into its slot too roughly. I hadn't thought of that - I might copy that if I remember next time. Interesting question. I've been driving normal automatics for many years and I think it's standard to hold the footbrake down while changing from D to R. I remember once riding as a passenger in my car while a mechanic tested it for a fault and he shifted from Drive to Reverse while the car was still moving, causing me to grit my teeth and hope he hadn't done any damage. On an automatic, the car is always moving if it's in Drive; it will edge forward even if you don't touch the accelerator. On standard automatics, there are mechanical bits and pieces that move when you change the gear selection, engaging and disengaging clutches in the gearbox to select the gear. But on the Lexus/Toyota hybrid transmission, nothing mechanical changes in the transmission when you move the gear selector from Drive to Reverse. All the cogs are permanently engaged. All that happens when you switch from Drive to Reverse is that the computer switches motor/generator 2 (MG2) into reverse. So I can't think of any mechanical damage that might be done by not applying the footbrake while you change gear. The engine is not affected; it may keep running or it may stay stopped, depending what it was doing at the time. There is no reverse gear as such, the car is just driven backwards by the electric motor. As for electrical damage, I don't know the answer. The other motor, MG1 is frequently changing the direction it spins, controlled by the computer, so my guess would be that MG2 would probably cope with being switched into reverse without any problem, too. I imagine the computer would be designed to protect it from any damage. If the car is nearly stationary it would be edging forward slowly, driven by MG2. If it then switches direction, I would have thought the designer would have made sure that it isn't harmed by excess current. But, as I say, this is just a guess. Having said that, I'd suggest it might be a bad habit to adopt. That's because even if it was safe to do this on this type of hybrid car, it's probably not advisable on a normal automatic and if you adopt it as a habit, you might do it on some occasion without thinking when you're driving a normal automatic, which I'd suggest is not advisable. As regards Neutral, it's important to remember that the high voltage battery is not being charged when the car is in Neutral. So it shouldn't be used when the car is parked, for example, for the passengers to enjoy the view for any length of time - always put it back into Park. The motor/generators are disconnected when Neutral is selected but if the car is moved, they will spin nonetheless. This means the car should not be towed at any speed, as the motor/generators might be damaged if they spin at high speed. I imagine Neutral is only there to allow the car to be winched onto a trailer at walking speed.

Another thing that was mentioned in the video was the temperature sensor on the larger battery. I think the battery on the IS300h also has a temperature sensor. Is that the same on the RX450h or have you found any details about whether this exists on alternative batteries?

That sounds normal. Here's a video about the transmission and this section shows what's called the parking pawl, which locks the transmission when you engage Park. So you can see that it's normal that there would be a bit of movement when Park is engaged. This is the same on all automatic cars, not just hybrid cars. (The video is actually about the P410 transmission which is for front-wheel drive cars. The equivalent is the L210 on the IS300h, which is a version used for rear-wheel drive cars but they work in much the same way.). But when you use the foot-operated parking brake, there really shouldn't be much movement of the car - certainly not "a few inches". There might be a bit of movement but it should feel more secure than when you just engage Park on the transmission.

I'm sure that's right that it's better to drive the car to keep it in good operating condition, mostly because the engine is running most of the time and generating electricity while it runs. But when the car is moving, some of the electricity has to be used to power motor/generator 2 (MG2) as the car won't move unless MG2 is turning. If MG2 has no power, the engine would just spin to no effect. While you're driving, the engine is also turning MG1, which can generate the electricity needed by MG2 and any spare power can be stored in the high voltage battery. Some of the engine power is also used to add torque to MG2's torque to drive the road wheels. So only some of the engine's power is left over to be stored as electricity in the high voltage battery. By contrast, if the car is stationary, all the engine power is used to drive MG1 and virtually all the electricity MG1 generates can be stored in the high voltage battery. So if you wanted the high voltage battery to be charged, it might be quicker to do it by driving the car, with the engine running most of the time, perhaps up to around 2,000 rpm or more. But in terms of petrol used, it would be more efficient to keep the car stationary. While the car is stationary and the engine is spinning at around 1,100 rpm, MG1 is turning at around 4,000 rpm. But when you drive the car at lowish speeds, as MG2 goes faster to drive the road wheels, MG1 goes slower generating less electricity. Until eventually at some point it will stop altogether and then start spinning in the opposite direction. So at town speeds MG1 is probably spinning more slowly and generating less electricity than when the car is stationary. Having said all that, I wouldn't have thought there's much need to charge the hybrid battery at all unless you're going to store the car for six months or more. Even on one bar of the gauge, the battery still has a 40% charge and most reports on this forum that I've seen say that it loses very little power over long periods of time.

I've been wondering about battery replacement too for when the time comes. I just came across this video which gives a few more details than I knew before about these AGM batteries. https://youtu.be/M53Hbh5wpRQ?t=257 I knew the original replacement batteries were irritatingly expensive. But now I've seen this video, I'm beginning to wonder if I'd be better to stick with the original specification rather than switch to a cheaper option. Over the lifetime of the battery, maybe the extra expense would be worthwhile spread over several years.

I've been trying to understand what's needed to keep the 12v battery charged while the car is not being used frequently. I don't have an easy way to connect a charger so I wanted to try and understand how the car charges the 12v battery in normal use. I'm sure this was obvious to a lot of people but for anyone else who was as unclear about it as me, I thought it might be useful to post what I've found out. I've found this video from Weber Auto, which has also done lots of other useful videos on how hybrid cars work, focussing mostly on the Toyota Prius.This one is about the 12 volt system. From what this clip says, it seems clear that you don't have to run the engine to charge the 12v battery. As soon as you turn on the car to the Ready state, the 12v battery is being charged with power from the high voltage battery via the inverter/converter. This, of course, will gradually run down the high voltage battery but then the engine will start to charge it up again. But apparently it makes no difference whether the engine is running for the 12v battery to be charged continuously at around 14.5 volts all the time the car is in the Ready state.

Glad to hear you've got it working. This reminds me that there are a couple of things I don't understand in this area which maybe the forum experts can answer. First, I tried revving the engine while in Park the other day and I noticed that the graphic display showed that the engine was charging the hybrid battery while idling but it stopped charging when I revved the engine. Does anyone know if this is a correct display of what is happening? Does the charging stop when you rev the engine? Might this be because MG1 (which does the job of an alternator) would be spinning too fast in this situation? I wondered if this could be right and I went back to my main reference point for understanding the transmission - this now fairly old but very useful page showing a graphic of how it works. If you scroll down to near the bottom of the page you'll see the working graphic of the power split device (You may have to permit Adobe flash to run to see this.) I deduced from this that on the early Prius that it represents, when stationary in Park with the engine idling around 1,100 rpm, motor/generator 1 (MG1) is turning at around 4,000 rpm. On the IS300h it's possible to cruise at 70mph with the engine turning at around 1,250 rpm - not much faster than its idling speed of 1,100 rpm. The IS300h is different, of course, but on the Prius graphic demo, if you set the speed to 70mph and the engine to around 1,300 rpm, MG1 is now spinning at around 6,000 rpm - but in the opposite direction! Now, I assume that it can generate electricity spinning in either direction. If that's the case and you want to charge the 12v battery, it might seem there's not a huge advantage to be got from driving at 70mph as compared to leaving the engine idling at 1,100 rpm. There's also the issue that when the car is stationary, I assume all the torque from the engine is driving MG1. By contrast, in the early Prius torque was split through the Power Split Device by 28% to MG1 and 72% to the road wheels. So maybe it's the case that when you're cruising at 70 mph only around a third of the torque is driving MG1, compared to 100% when you're stationary. Can some expert confirm if this is right or not and point out where I've misunderstood what's going on? If the above is right, it seems to suggest that to charge the 12v battery, it may be more effective to keep the car stationary rather than cruising down a motorway.

I was wondering the same. I'm not very familiar with what these numbers mean - I haven't given it much thought since school days!. Not trusting myself to remember the formula (V=I/R or something like that?) I looked it up on the internet and found this page that says 15 amps on a 12 volt circuit equals 180 watts. If this is right (please, someone, correct if it's wrong) this is easier for me to relate to - a bit less than a couple of 100 watt bulbs. That sounds a bit high to start a computer circuit or two. But there must be some sort of relay to open the hybrid battery circuit - maybe there's a physical electro-mechanical switch to open it. If that's the case a brief supply of 180 watts might be possible. But it probably takes only seconds to get the hybrid circuit to the ready state, so the 15 amps probably doesn't depend solely on the 12V circuit for very long. It'll be interesting to see some more details.

Absolutely. Very sophisticated. Just not sure it's using a neural network in its usual meaning.

Actually, I didn't find this as interesting as I hoped. There may be more to it, but to me this just seems a complicated way of saying they measure temperature inside and out, plus heat from sun, then adjust airflow temperature, speed and direction accordingly. I'm not sure that this is a big step forward in car aircon but I'm probably missing something. A genuine big next step for car air conditioning would be to take into account how hot the driver and passengers are feeling. A sensor to measure their forehead temperatures could feed data to the aircon system and increase or decrease airflow and temperature accordingly. (Maybe this has already be developed.) As an added benefit it could also tell you if you've got coronavirus. (The microphone would have been counting how often you cough). If the car comes up with a positive diagnosis, the windows would close and the doors would lock and the hazard lights would flash until soldiers dressed in hazmat suits arrived to take you away to an isolation unit.

That sounds interesting. Does it say what the three layers are?

Many thanks for the explanation. I didn't realise there was no need to run the air conditioning regularly when the compressor is electric, unlike in conventional cars. That means I can turn it off for part of the year and save some fuel!

I saw that email too. There might be an argument for running the air conditioning once a week too. There are the usual arguments that the seals will dry out if you don't use it and it will then lose gas or worse, start to seize up. Repairs for the air conditioning could well be more expensive than buying a new 12v battery. I think I will keep my air conditioning going when I run the car from time to time.

The first is a difficult question. What you're asking is will the car keep running for 16 years, reaching 120,000 miles by then? The answer, I suppose, is "we can't tell but probably yes", judging by the number of 16 year old Lexuses still around.For example, the HowManyLeft website shows that of around 32,000 IS200 cars registered in 2004, around 16,000 are still on the road or registered SORN. But what you also probably want to know is will it still be reliable or will it cost a lot to maintain. Anecdotally, the answer seems to be that Lexus is usually the most reliable brand in surveys. I keep cars for a long time, too. So part of what attracted me to the hybrid IS300h was the fact that of things that might go wrong it has no gearbox, no starter motor, no alternator as such, no clutch; instead it has two electric motors. In my experience, electric motors last for ages without attention but whether that means the same for a hybrid car I have yet to find out. Brakes, too, can get away with very little wear. After 50,000 miles, my brakes are around a quarter to one-third worn. That suggests they might last for 150,000 miles but we'll see, of course. The cost of servicing at Lexus dealers is not cheap, though five-year-old cars get a discount. Service is due every year, unlike some German cars which might get away with every two years. One thing to bear in mind is that the IS300h 60,000 mile service is an expensive one because the spark plugs are replaced every 60,000 miles. The 100,000 mile service is expensive, too, but I can't remember what is done to increase the cost. But so far, I've had no extras charged when I've had the car serviced - unlike with German cars, where an extra unexpected £500 was fairly common.in my experience. More than once the Lexus dealer has also changed the windscreen wipers without charge. It doesn't cost them much to do this but it's nice that they do something without charge.

In the manual it says if the car isn't going to be driven for a while you can deactivate the smart entry/start system. I assume this stops the car searching for the key signal continuously. I imagine it continues to do this even when you turn off the key signal on the key itself. In any case, the manual seems to suggest that after five days the car will search less frequently anyway to save power. I wonder if there is much power to be saved by deactivating the smart enry/start. Will it have much impact on saving the power in the 12v battery? Does anyone know how much power would be saved and whether it's worth bothering with this?

I can't think of a reason why slow town driving would be more detrimental to the hybrid battery than motorway driving. The battery doesn't see any indication of driving conditions - it simply calls for power from the engine whenever it needs charging. Driving conditions won't have any impact on that as far as I can see. The hybrid battery is guaranteed for 15 years now, as long as you get a hybrid health check done I think every year or 10,000 miles. But short trips will have an impact on the mpg especially in the winter. I wrote a post about this a couple of years ago, which I'll link to below. This is a consistent pattern that fuel consumption tends to increase (lower mpg) in winter and gets better again in the summer.

It turns out I was wrong. Further investigation shows that on the IS you can rev the engine while in Park and in any mode (Eco, Normal, Sport). The accelerator pedal is misleading because it doesn't react as a conventional car would when you begin to press it. So although a fairly light touch will get the car moving in Drive, nothing happens for the same amount of pressure when you're in Park. But when you press it a bit further the engine will rev. I don't know if there's a limit to how fast you can rev the engine; I didn't press it very far. But I noticed something else that's interesting. With the car in Park and without touching the accelerator, the graphic displays show that the engine is charging the hybrid battery. But if you rev the engine, it stops charging the hybrid battery, according to the graphic displays. If this accurately represents what is going on, I imagine Motor Generator 1 (MG1) is allowed to spin freely without any load because with the car and MG2 stationary, it could damage MG1 if it was spinning faster than its generating capacity allowed. Or maybe there's some other reason. Either way, it looks as though on the IS the generation stops when you rev the engine and the car is in Park..

It may work differently on different models. On the IS I have the impression that in Normal mode the accelerator is disabled in Park whether you have your foot on the brake or not. That's to say, you can't rev the engine while the car is stationary in Park. But just a couple of days ago I discovered that you can rev the engine in Park when you select Sport mode. Not really my area of expertise, but I imagine this is important for people who like racing the adjacent car away from the lights and you need to blip the engine menacingly while the lights are still red.

Hadn't thought of doing this. Does it make a difference being in Drive rather than Park? If the engine is running, doesn't it charge the hybrid battery while it's in Park as well?

And here he is 54 years ago. Hard to believe! Featuring the up and coming Eric Clapton.