Hesitation problem at various speeds (TSB info post #159)
01-17-19, 05:11 PM
#961
Software driven many gear shift tranny's purpose is to improve MPG for sure. Being software controlled, it ought to be learning tranny. I moved from Lexus to Benz.
Manual does not explain the complexity how it's proven 7 speed tranny works but shows how to reset(putting it to relearn mode) the box. It is done from driver's seat
with specific steps which takes about ~10 minutes. One can repeat the procedure multiple times to get the best out of it.. Then it'll learn your driving style(habits). I know
2015 Acura MDX had issues which made me to dump it. Lexus RX has same issues. But Audi 8 speed and BMW X5 8 speed, Benz 7 speed ones don't show this problem.
IMO, Lexus needs to improve it's software.
Manual does not explain the complexity how it's proven 7 speed tranny works but shows how to reset(putting it to relearn mode) the box. It is done from driver's seat
with specific steps which takes about ~10 minutes. One can repeat the procedure multiple times to get the best out of it.. Then it'll learn your driving style(habits). I know
2015 Acura MDX had issues which made me to dump it. Lexus RX has same issues. But Audi 8 speed and BMW X5 8 speed, Benz 7 speed ones don't show this problem.
IMO, Lexus needs to improve it's software.
01-17-19, 06:17 PM
#962
Driver School Candidate
I was talking about the 2017 MY, but it should be applicable to all years as far as I know. I remember reading somewhere that it would learn the way you drive, I can't find it on a quick search and frankly I don't feel to go through the manual on a semantic quest.
As far as I know all AT have been adaptive/learning for the last 15 or so years, it was supposed to be "Progress" but the so called primitive engineering of the cars of the 50s is still going strong albeit with ingenuity (Cuba) I wonder if our techno riddled conveyance will do the same
P.S. Look also ate HTONY post just before this one where he too says that it's a learning transmission
As far as I know all AT have been adaptive/learning for the last 15 or so years, it was supposed to be "Progress" but the so called primitive engineering of the cars of the 50s is still going strong albeit with ingenuity (Cuba) I wonder if our techno riddled conveyance will do the sameP.S. Look also ate HTONY post just before this one where he too says that it's a learning transmission
Lexus RX 350
The 2019 base RX 350 trim has an MSRP of $43,570. For that price, you’ll get NuLuxe leatherette upholstery, power-adjustable front seats, dual-zone automatic climate control, proximity keyless entry, push-button start, rain-sensing windshield wipers, a rearview camera, automatic high beams, a pre-collision warning and braking system with pedestrian detection, adaptive cruise control, lane departure warning, and lane keep assist. This SUV also has Siri Eyes Free, HD Radio, satellite radio, a nine-speaker stereo, two USB ports, Bluetooth, and a multimedia system with Scout GPS Link and an 8-inch display.
01-17-19, 10:07 PM
#963
Lead Lap
This from page 685 of my owner's manual: Select octane rating 87 (Research Octane Number 91) or higher. Use of unleaded gasoline with an octane rating lower than 87 may result in engine knocking. Persistent knocking can lead to engine damage
I see this as warning You OTOH sees it a recommendation
I don't want to argue either
I see this as warning You OTOH sees it a recommendation
I don't want to argue eitherIt says "Select octane rating 87 (Research Octane Number 91) or higher.", surely that means you drive into service station and select 87. Obviously you can ALWAYS use a higher octane fuel, won't hurt it but as that states they say or recommend to use Regular 87 and nothing less.
I just re-searched the entire 2019 owner's manual, all 777 pages, and nowhere does it say anything like "transmission learns your way of driving." In fact, the two words "transmission" and "learn" do not coincide in the same sentence anywhere in the owner's manual.
I'd really appreciate it if you can you tell me what page it says this in your owner's manual, and which year owner's manual you see it in? Or maybe if you could possibly be mistaken?
I really think this is a technical mis-conception that is worth clearing up for people on this forum if at all possible. Because any mis-information can only cause confusion for others. Please can you provide solid evidence, not conjecture, such as pictures, links or page numbers that Lexus states their transmissions are adaptive transmissions or other similar wording?
Thank you for helping get to the bottom of this,
I'd really appreciate it if you can you tell me what page it says this in your owner's manual, and which year owner's manual you see it in? Or maybe if you could possibly be mistaken?
I really think this is a technical mis-conception that is worth clearing up for people on this forum if at all possible. Because any mis-information can only cause confusion for others. Please can you provide solid evidence, not conjecture, such as pictures, links or page numbers that Lexus states their transmissions are adaptive transmissions or other similar wording?
Thank you for helping get to the bottom of this,
I was talking about the 2017 MY, but it should be applicable to all years as far as I know. I remember reading somewhere that it would learn the way you drive, I can't find it on a quick search and frankly I don't feel to go through the manual on a semantic quest. As far as I know all AT have been adaptive/learning for the last 15 or so years, it was supposed to be "Progress" but the so called primitive engineering of the cars of the 50s is still going strong albeit with ingenuity (Cuba) I wonder if our techno riddled conveyance will do the same
P.S. Look also ate HTONY post just before this one where he too says that it's a learning transmission
As far as I know all AT have been adaptive/learning for the last 15 or so years, it was supposed to be "Progress" but the so called primitive engineering of the cars of the 50s is still going strong albeit with ingenuity (Cuba) I wonder if our techno riddled conveyance will do the sameP.S. Look also ate HTONY post just before this one where he too says that it's a learning transmission
THIS IS FROM THE US NEWS REPORT ON THE 2019 LEXUS RX: https://cars.usnews.com/cars-trucks/lexus/rx-350Lexus RX 350
The 2019 base RX 350 trim has an MSRP of $43,570. For that price, you’ll get NuLuxe leatherette upholstery, power-adjustable front seats, dual-zone automatic climate control, proximity keyless entry, push-button start, rain-sensing windshield wipers, a rearview camera, automatic high beams, a pre-collision warning and braking system with pedestrian detection, adaptive cruise control, lane departure warning, and lane keep assist. This SUV also has Siri Eyes Free, HD Radio, satellite radio, a nine-speaker stereo, two USB ports, Bluetooth, and a multimedia system with Scout GPS Link and an 8-inch display.
The 2019 base RX 350 trim has an MSRP of $43,570. For that price, you’ll get NuLuxe leatherette upholstery, power-adjustable front seats, dual-zone automatic climate control, proximity keyless entry, push-button start, rain-sensing windshield wipers, a rearview camera, automatic high beams, a pre-collision warning and braking system with pedestrian detection, adaptive cruise control, lane departure warning, and lane keep assist. This SUV also has Siri Eyes Free, HD Radio, satellite radio, a nine-speaker stereo, two USB ports, Bluetooth, and a multimedia system with Scout GPS Link and an 8-inch display.
->>>>>>>>>>>>>>>>>Not a toyota engineer, but from the press release I think what everyones on about is the "AI-Shift"
Sport AI shift control
Lexus Sport AI (artificial intelligence) shift control is a transmission algorithm designed to manage the shift regime according to road conditions and driver intention, thereby optimising the characteristics of the turbo engine.
It includes Driver-intention Control, Sudden Braking Downshift Control and G-AI Shift Control.
Driver-intention Control monitors accelerator usage and vehicle condition to provide gear shift patterns that suit sporty driving.
G-AI Shift Control uses G-sensor information to help set up for a corner and ensure optimum response when re-acceleration occurs.
It combines the RX 200t features of Drive Mode Select (DMS) and the new G-sensor when the transmission is in D (automatic) mode.
The system selects the most suitable gear for sporting driving by monitoring the status of the vehicle's G sensor, with shifting selection biased towards the lower gears to draw out the full potential of the turbocharged engine.
When entering a corner in the D range with SPORT mode selected, the vehicle condition is determined using information gathered from the G-sensor and driver operations, and the transmission downshifts to the optimum gear. While cornering, the gear is held to enable powerful acceleration at the corner exit.
Powertrain Cooperative Control
Powertrain Cooperative Control uses information based on driver operations, vehicle condition and driving environment to match engine and transmission settings and optimise driveability.
In DMS SPORT mode, the targeted drive force and gear range are set according to accelerator pedal angle to provide a sportier driving experience and acceleration from the turbo engine.
Lexus Sport AI (artificial intelligence) shift control is a transmission algorithm designed to manage the shift regime according to road conditions and driver intention, thereby optimising the characteristics of the turbo engine.
It includes Driver-intention Control, Sudden Braking Downshift Control and G-AI Shift Control.
Driver-intention Control monitors accelerator usage and vehicle condition to provide gear shift patterns that suit sporty driving.
G-AI Shift Control uses G-sensor information to help set up for a corner and ensure optimum response when re-acceleration occurs.
It combines the RX 200t features of Drive Mode Select (DMS) and the new G-sensor when the transmission is in D (automatic) mode.
The system selects the most suitable gear for sporting driving by monitoring the status of the vehicle's G sensor, with shifting selection biased towards the lower gears to draw out the full potential of the turbocharged engine.
When entering a corner in the D range with SPORT mode selected, the vehicle condition is determined using information gathered from the G-sensor and driver operations, and the transmission downshifts to the optimum gear. While cornering, the gear is held to enable powerful acceleration at the corner exit.
Powertrain Cooperative Control
Powertrain Cooperative Control uses information based on driver operations, vehicle condition and driving environment to match engine and transmission settings and optimise driveability.
In DMS SPORT mode, the targeted drive force and gear range are set according to accelerator pedal angle to provide a sportier driving experience and acceleration from the turbo engine.
However, seeing what other makers have traditionally called an adaptive transmission is quite funny. Adaptive transmissions have typically been pre-programmed maps of typical uses typically limited to 5-10 presets. Whichever your driving style is closest to, it adapts the powertrain too. The newer systems typically feed more live data, to be more precise, and with the advant of drive modes, these have gone from behind the curtains to labeled how you like when you like. Lets be real here, AI processing would require lots of raw hardware power, that heck Lexus fails to include for the infotainment, do you really believe theres an AI hardware controller installed on these vehicles at this price point, a vehicle primarily suited for mall duty....Not a knock on the product, just saying.
01-18-19, 09:40 AM
#964
Pole Position
Lots of people seem to have the wrong idea about what an Adaptive Transmission is.
An adaptive gearbox does indeed learn the style of the driver - but over minutes, or a small number of shifts, not over a long period of time such as thousands of miles since the last ECU reset.
Essentially, if you start to brake hard and accelerate hard it'll automatically start to go into a sport mode where it delays upshifts and downshifts earlier. Then if you back off to a more economical pace the gearbox will automatically respond by shifting up earlier and generally using higher gears. This is what adaptive transmission means.
Lexus does not indicate anywhere that they use this type of automatic adaptive transmission. In fact, we know our Lexus' can manually adapt the transmissions when we manually switch between Eco, Normal and Sport modes. But this process is not automatic.
I know that the ECU reset procedure people frequently mention can potentially make a difference in perceived performance for a little while by resetting long-term memory values such as idle speed, throttle/fuel usage, spark, trim gain values on the injectors, sensor and actuator values as well as diagnostic trouble codes. But one thing the values do not seem to include is shift points. Resetting the ECU is not something you should do as a matter of routine maintenance. All of these values saved by the ECU are largely beyond the control of the driver.
While some very expensive or sporty cars have had automatic adaptive transmissions in the past, it is an apparent myth that the RX 350's transmission learns and responds automatically to the driver's driving style.
Think about this hypothetical for a moment.... If I'm in the market for a used 2017 RX 350 and I've found two sellers with ~ 50,000 miles on each. One was driven by a grandmother slow as can be, the other was driven by a 22 year old speed demon who constantly floors the vehicle. Are you saying the RX 350 driven by the speed demon would appear to perform better than the RX 350 driven by grandma? I can't imagine Lexus would knowingly allow this type of ECU behavior to hamper grandma's ability to resell her car or drive it safely by hampering it's performance. The buyer would think there's something wrong with grandma's car (even though it's the better buy) and buy the ragged on speed demons car instead simply because it performs better? That just cannot be right.
This whole adaptive transmission thing is a myth it's time to dispel.
The ECU reset procedure does not change transmission behavior, but it does temporarily change behavior of other parts of the engine mostly relating to fuel delivery.
An adaptive gearbox does indeed learn the style of the driver - but over minutes, or a small number of shifts, not over a long period of time such as thousands of miles since the last ECU reset.
Essentially, if you start to brake hard and accelerate hard it'll automatically start to go into a sport mode where it delays upshifts and downshifts earlier. Then if you back off to a more economical pace the gearbox will automatically respond by shifting up earlier and generally using higher gears. This is what adaptive transmission means.
Lexus does not indicate anywhere that they use this type of automatic adaptive transmission. In fact, we know our Lexus' can manually adapt the transmissions when we manually switch between Eco, Normal and Sport modes. But this process is not automatic.
I know that the ECU reset procedure people frequently mention can potentially make a difference in perceived performance for a little while by resetting long-term memory values such as idle speed, throttle/fuel usage, spark, trim gain values on the injectors, sensor and actuator values as well as diagnostic trouble codes. But one thing the values do not seem to include is shift points. Resetting the ECU is not something you should do as a matter of routine maintenance. All of these values saved by the ECU are largely beyond the control of the driver.
While some very expensive or sporty cars have had automatic adaptive transmissions in the past, it is an apparent myth that the RX 350's transmission learns and responds automatically to the driver's driving style.
Think about this hypothetical for a moment.... If I'm in the market for a used 2017 RX 350 and I've found two sellers with ~ 50,000 miles on each. One was driven by a grandmother slow as can be, the other was driven by a 22 year old speed demon who constantly floors the vehicle. Are you saying the RX 350 driven by the speed demon would appear to perform better than the RX 350 driven by grandma? I can't imagine Lexus would knowingly allow this type of ECU behavior to hamper grandma's ability to resell her car or drive it safely by hampering it's performance. The buyer would think there's something wrong with grandma's car (even though it's the better buy) and buy the ragged on speed demons car instead simply because it performs better? That just cannot be right.
This whole adaptive transmission thing is a myth it's time to dispel.
The ECU reset procedure does not change transmission behavior, but it does temporarily change behavior of other parts of the engine mostly relating to fuel delivery.
01-18-19, 09:45 AM
#965
Pole Position
Lexus may feel that there's no need to advise you that it's an adaptive transmission, it's a technical side of the vehicle that most people aren't interested in. Like ABS, the manual doesn't tell you how it works it just does it's thing when required or AWD, the manual doesn't explain that the drive is transmitted to the front wheels and to the rear wheels as required and that it can be constantly changing.
I too am under the belief that it is an adaptive transmission, my own experience with the car driving like a dog initially and then having the ECU reset by the dealer which fixed (mostly) my problem. I didn't mention the resetting to them only about the way it drove, they said when I collected the after the service then reset the ECU.
I too am under the belief that it is an adaptive transmission, my own experience with the car driving like a dog initially and then having the ECU reset by the dealer which fixed (mostly) my problem. I didn't mention the resetting to them only about the way it drove, they said when I collected the after the service then reset the ECU.
01-18-19, 09:49 AM
#966
Pole Position
I was talking about the 2017 MY, but it should be applicable to all years as far as I know. I remember reading somewhere that it would learn the way you drive, I can't find it on a quick search and frankly I don't feel to go through the manual on a semantic quest. As far as I know all AT have been adaptive/learning for the last 15 or so years, it was supposed to be "Progress" but the so called primitive engineering of the cars of the 50s is still going strong albeit with ingenuity (Cuba) I wonder if our techno riddled conveyance will do the same
P.S. Look also ate HTONY post just before this one where he too says that it's a learning transmission
As far as I know all AT have been adaptive/learning for the last 15 or so years, it was supposed to be "Progress" but the so called primitive engineering of the cars of the 50s is still going strong albeit with ingenuity (Cuba) I wonder if our techno riddled conveyance will do the sameP.S. Look also ate HTONY post just before this one where he too says that it's a learning transmission
There was not a single mention of Adaptive/Learning Transmission technology.
Just trying to get to the bottom of it all.
01-18-19, 09:53 AM
#967
Pole Position
Happy trails everyone.
01-18-19, 09:54 AM
#968
Intermediate
I just searched the 2017 Owner's Manual, too. Only took a couple of minutes using the Find feature on the PDF version on their website to scan through all mentions of the word transmission and read each instance in which it was used.
There was not a single mention of Adaptive/Learning Transmission technology.
Just trying to get to the bottom of it all.
There was not a single mention of Adaptive/Learning Transmission technology.
Just trying to get to the bottom of it all.
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Cocal (01-18-19)
01-18-19, 10:03 AM
#969
Pole Position
I'm trying to dispel the myth that one can do an ECU reset to delete saved values that change the way the transmission itself shifts.
01-18-19, 10:15 AM
#970
Yes but AI-Shift is a different technology that uses real-time input not saved data such as shift points, etc. built up over thousands of miles and whose data values can be reset by an ECU reset. Agreed? I'm trying to dispel the myth that one can do an ECU reset to delete saved values that change the way the transmission itself shifts.
01-18-19, 10:25 AM
#971
Pole Position
I think the confusion stems from the adjective "Adaptive" The tranny doesn't save any settings beyond a small amount collected over a few days after reset. This AI determines how you drive and how much response to give to your input. In this way it is adaptive in that it has adapted/leaned your way of driving and now knows how to respond. There is no data bank to go to the computer doesn't go that far.
In any event, your post is shifting closer to why I am positing that an ECU reset does not affect transmission behavior. Even if what you said was true, and a few days of data are saved and used in the AI-Shift algorithm, (it'd probably be more like minutes not days), then what are people to do? Keep resetting their ECU every few days? That's just not how this works, IMO.
Sorry if I sound crass in any way I don't mean to I'm just looking for absolute proof that an ECU reset can affect transmission shift points. It seems to be a myth.
01-18-19, 10:29 AM
#972
Intermediate
Yes but AI-Shift is a different technology that uses real-time input not saved data such as shift points, etc. built up over thousands of miles and whose data values can be reset by an ECU reset. Agreed?
I'm trying to dispel the myth that one can do an ECU reset to delete saved values that change the way the transmission itself shifts.
I'm trying to dispel the myth that one can do an ECU reset to delete saved values that change the way the transmission itself shifts.
01-18-19, 10:37 AM
#973
Did you read that in any official Lexus documentation, website, brochures, etc.?
In any event, your post is shifting closer to why I am positing that an ECU reset does not affect transmission behavior. Even if what you said was true, and a few days of data are saved and used in the AI-Shift algorithm, (it'd probably be more like minutes not days), then what are people to do? Keep resetting their ECU every few days? That's just not how this works, IMO.
Sorry if I sound crass in any way I don't mean to I'm just looking for absolute proof that an ECU reset can affect transmission shift points. It seems to be a myth.
In any event, your post is shifting closer to why I am positing that an ECU reset does not affect transmission behavior. Even if what you said was true, and a few days of data are saved and used in the AI-Shift algorithm, (it'd probably be more like minutes not days), then what are people to do? Keep resetting their ECU every few days? That's just not how this works, IMO.
Sorry if I sound crass in any way I don't mean to I'm just looking for absolute proof that an ECU reset can affect transmission shift points. It seems to be a myth.
01-18-19, 10:42 AM
#974
Lexus Champion
Yes but AI-Shift is a different technology that uses real-time input not saved data such as shift points, etc. built up over thousands of miles and whose data values can be reset by an ECU reset. Agreed?
I'm trying to dispel the myth that one can do an ECU reset to delete saved values that change the way the transmission itself shifts.
I'm trying to dispel the myth that one can do an ECU reset to delete saved values that change the way the transmission itself shifts.
from driver and engine to learn and decide. If you keep putting the gear box into learn mode repeatedly the refinement gets even better. I tried
and many other Benz drivers agree with this. I am the only one driving my car in this case. ECU and TCU work together in asynchronous way
not synchronous. Different manufacturers write their own software so there is difference between their cars. I am sure some of them even using
quantum processing to get their software modules.
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Cocal (01-18-19)
01-18-19, 11:09 AM
#975
Lexus Champion
Last night I searched Youtube about this. When I use Mercedes Benz as keyword there were many hits, for Lexus I did not
get any.
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Cocal (01-18-19)
