DunWkg

It's been said the 450 learns how we drive.

If we drive poorly (not economically) does it counteract this and try to improve your bad habits or does it compliment your bad habits and respond favorably? If, let's say, you drive rapidly from stop signs, does it retard accelerator response further or kick in gas sooner because you like to speed away?

Will the car learn two different patterns? If I drive extremely conservative in ECO mode and heavy footed in NORMAL mode, will it learn and compliment the two patterns or create some average of the two?

Does learning only take place in the first days/weeks/months of ownership or if I start driving differently a year later will it learn the changes?

Is a complete power down (disconnect 12 volt battery) the only way to refresh or restart learning?

Or can my dealership refresh learning via their plug-in laptop?

Does the car really learn or is that just rumor/gimmick/advertising?

Cruiter

Interesting question and yes I've heard that too but not from a definitive source.

Wouldn't it be nice if we could get an engineer to drop into the forums every so often to answer questions like that.

The G Man

The adaptive transmssion software will learn one's driving habit. If you are a eco minded driver, the transmssion will up shift at a lower rpm and for the more aggressive drivers, it will hold a lower gear longer. Some adpative transmission also alter the throttle mapping as well, not sure if the RX350 does that. Usually the learning program can average up to a few thousand miles of data. Some owners in the pass had success with disconnecting the battery for 15 mins or so to reset the program and the dealer can do it with a lap top as well. With that said, the RX450h's CVT have no gears, so everything I said above might not apply. If anyone have any info on rather the RXh's CVT is adaptive or not or how it works, do share.

RXSF

My first instinct was that the CVT doesnt need to learn when to shift so an adaptive software for it may not be very helpful or necessary. However, i have noticed that the computer that controls whether or not the engine stays on or turns off is quite clever too so perhaps that computer is adaptive.

for instance, have you noticed that after you go up a hill and need a lot of power (way into the white area) that the engine will continue to stay on even after you are on level ground and are traveling at low speeds? It knew that you needed power and still thinks that you might need the power.

Sames goes for just flooring it on level ground. If you keep driving aggressively, it will not turn off the engine at all until you are fully stopped and remain stopped for a few seconds

kitlz

David, I think we learn from the 450h, not the other way around. I bought mine for a multitude of reasons, one being a concerted effort to drive more efficiently and cleaner. A positive side effect is increased mileage. It's become a game. If the mileage drops without a precipitous change in temperatures, I realize I need to change my driving habits. The 450h responds positively to this kind of behavior modification.

The G Man

When you are gunning the engine, the electric motors are drawing full power as well. Maybe the engine stays on to charge up the batteries afterward.
I know one of the biggest factor of how long and when the engine stays on or off is temperature. In cold weather, the engine is on most of time.

DunWkg

Being an economical driver is not in my genetics, however if the RX and I can relearn I would consider resetting the computer. I would try hard only in ECO mode and a short(?) period of time for the training period. In normal mode, give me back throttle response.

The other obvious option is live with 26-28 mpg. Which isn't too bad.

I haven't tried digging through the TechInfo web site yet. I could try that too, there may be information there.

The G Man

If you drive a certain way for a few thousand miles, it will adopt to your style of driving, but like I mentioned before, I am not sure if the RXh can adopt at all. It is design with fuel economy in mind and there is no gears shift pattern to adjust. I dont think Lexus adjust the hrottle mapping either, It doesnt make any sense for Lexus to adjust the throttle mapping to suit the more aggressive drivers, so I am guessing the throttle map leaned more toward the consevative side.
To tell you the turth, I think 26-28 mpg is about average. My wife drives about 2 mile to work and try to take long trips with the RXh on the weekend and she only gets about 23 to 24 MPG. She does not hypermile either.

Traveler1

JP Patent 2001-020771 describes that the hybrid ECU(HV ECU) refers the previous driving tendency of "consuming fuel" side or "consuming battery" side, to decide torque generation. The tendency is decided
by calculating difference between the starting SOC(State Of Charge) and the ending SOC of last driving. If the value is minus, then HV ECU decides "This driver uses motor much more than engine" so that, to correct the balance, HV ECU uses much more engine to get torque. If the value is plus, HV ECU uses much more motor than engine.
In my experience, I believe the ECU learns as above. Unfortunately my RX keeps lower SOC at home because it is on the hill (250ft) and the town is lower, so engine works well to charge despite downhill is here every time I go out... Please try keeping higher SOC, then you may observe saving fuel.

The G Man

That sounds more like a program to determine rather to use the electric motor or ICE depending on the state of charge of the batteries.

Traveler1

The paper says that the tendency makes the tire torque ratio of the ICE and the electric motor(MG2), meanwhile, the difference between the current SOC and the target SOC(eg., 60%) makes the generated power(MG1 with ICE) to "recharge" or "drive electric motor". It sounds confusing...
So the "discharge" type driving may cause "fuel consumable" driving. In that case, if the soft acceleration is in the first eco zone(green) on the power meter next to speed meter to avoid using ICE, then motor torque is weak, that's just my feeling. If you do "discharge" type drive, the next "charge" type drive may recovers the memory status (I believe twice of "charge" drive recovers perfect).
# I do not know if the patent has been applied on my RXh or not, anyway. Please try and share the result.

Traveler1

It would be nice if the HV ECU has 2 or more memories depend on the driver (or key), but it looks it doesn't. Your partner may reset/recover!? the status. LoL

DunWkg

I would like ECO mode memory and non-ECO memory, although memory by fob would be interesting as our second driver is the economical driver.

The G Man

Ahhhhhh. I understand what you are saying now, depending on one's driving habit and the battery's charge, the ECU will decide rather to use the electric motor, ICE or both when accelarating. That kind of explain why the ICE always kicks in on our RXh, my wife does not hypermile.
Instead of having two driving profiles in the memory, Lexus can simply have a sport mode like many other SUV.

Traveler1

That's quite understandable. Conceptually to say, sports mode release you from your "solemn" eco-driving manner as exceptional way, right? RXh might have it to leverage its high power.

I enjoy full power throttle, but also I enjoy fuel cut driving on the high way. You can recognize the fuel cut(F/C) status through the instance MPG bar chart on the multi monitor display. You can see the full bar (ie. max of MPG) when you drive (mild) downhill with soft gas pedal (power meter indicates 0 between green and blue), as driving like a free fall. HV ECU recognizes the slope to leverage the gravity. It's one of the way to earn better MPG, I think.