Transmission Adaptive Learning

Okay, so in the Orange Virus ECU Alpha Tuning thread within this forum, many members report that their 3rd Gen Tacoma with the V6 and an automatic transmission shifted gears and held speed just fine when the truck was new, or immediately after clearing the ECU's memory via a battery disconnect. But within 100 miles or so, the transmission 'learned' the owner's driving style, and adjusted the transmission's shift points and willingness to downshift to suit that particular driver. This adaptive learning is a bragging point feature of our trucks. Yet, these same owners who liked the shifting patterns initially, generally and strongly DISLIKED how the transmission behaved after learning and adjusting.

Can anyone explain to me how our trucks' ECUs can assess a driver's style, and then adjust the transmission to that style, and yet in so doing, infuriate the driver? Seriously, I'm just trying to understand how Toyota's efforts to please us as drivers can have the oposite effect so frequently. What data is the ECU examining, and how do they use that data to alter the transmission in a way that many of us find decidedly inferiour?

Thanks....................... Frank

 

While I have no exact knowledge of the data they are collecting , having lately retired from Toyota N America as a Elec Eng dealing with multi robot interface comms used during assembly. In answer to your inquiry , I would think at a minimum , I would want to collect data from, RPM , Throttle Posit. , Load Demand , Gear #, shift points , plus I am sure there are many more, just not my area of knowledge. So , now how to do something with this data. Using some specific calculations, along with graphing software, a 3 D image can be display by combining the data as selected , any data shifts or points that are deamed out side the norm, based on this graph, can be altered to improve smoothness. On my end of the Toyota building process, this is almost standard procedure, always doing Kaizan's , ( continuous improvement ), to advance this process.

 

My Transmission shifts fine. Except on the highway with the cruise control on.

 

Good to know. That may work for you, but I do a lot of highway with cruise.

 

yep.....mine too...hiwhway with cruise sucks big time if you are not on flat ground.....

 

I find sometimes it is better to take cruise off on some hills.

 

I believe the root of the problem is that the transmission "learning" is designed to increase MPG, rather than bolster the driver experience.

 

Here's a pdf on the A760(Tundra); it has some info on AI shift control.

 

I wouldn't mind a tune that replaces all of their adaptive maps with one, single predictable map. Call me crazy but I like the gas pedal to do the same thing every time I push it.

Let me adapt to the traffic or road conditions.

It's funny that they did this for MPG, because I get a solid 1-2 MPG more with the shift sense pro mapping. Which seems to me at least to be much more predictable.

 

"I wouldn't mind a tune that replaces all of their adaptive maps with one, single predictable map. Call me crazy but I like the gas pedal to do the same thing every time I push it. Let me adapt to the traffic or road conditions."

This is precisly what many on the Alpha ECU Tuning thread are advocating........................... Frank

 

Thank you for that rather long, detailed .pdf. It was more than I can understand, but toward the end I did grasp that the logic used for adaptive learning is quite sophisticated.

That said, I believe that the gentleman who wrote "I believe the root of the problem is that the transmission "learning" is designed to increase MPG, rather than bolster the driver experience." is likely correct. I simply misunderstood what the learning was trying to do.

Thanks for your help....................... Frank

 

it's kind of hilarious though - I can drive around town in S-4 and get about the same (sometimes better) than when it's always trying to race up to 6th in slow moving zones. Hell, I generally don't see more than a 1 mpg hit in ECT so while I know this may have been the intent, the sheer volume of shifting seems to consume as much fuel unless at cruise where 6th makes sense...

 

Fill it and get the ECU update... worked for me.. (make sure it is full)... don't settle for their BS that they checked it with the "puter"..!!

 

It's full, I just find driving into the wind or climbing a small hill with the cruise on. it will downshift way easier then it would if I was driving without the cruise on. My wifes highlander is similar in that aspect.

 

I totally agree... I recently drove to BC, from Ontario and got up to 28.9 MPG CDN..... I use cruise all the time on HWY.... BUT.. I personally filled the tranny (was down 1.5 Liters)..greased the zerks and filled the Rear and front diff....
Now I know the Cruise Control is very "aggressive" on the 2nd gens and this one also (especially Because it don't want to shift down)..

I found the way to get the best MPG is to run in "S" mode and when you see a hill coming, pull her into 5th, when YOU think you should (the ECU is always too late)...... that way she don't wait till it's too late and go ballistic to 4th gear.... I just run up and over the hill in 5th and then it moves back to 6th because I've pushed the knob forward at the hill top...

All is fine... The damn tranny is stupid crazy about saving gas.... and cannot see the hill coming (maybe they should put in a front camera to view the hill coming and then tell the tranny to shift more appropriately)..??

You listening TOYOTA..?? Might be a good idea..!!

 

Toyota is priding themselves on a mid size truck getting over 20MPG combined with strict EPA testing. They aren't really concerned how you "feel" driving it because on paper it looks better and that's what sells. Unfortunately the majority of owners are NOT complaining about the driving characteristics of this, so nothing will change from the factory side.

Hence why aftermarket tunes solve this need to the fewer. Me being one of them.

 

Technology is great when it works...Is Toyota trying to enhance the owner/driver's experience or are they adding more "technology" that some engineer thought would be a good idea and help sell more vehicles? Whatever the reasoning the bottom line is...is the owner happy or even satisfied with the product they just purchased? My new 2017 TRD OFF ROAD with the automatic transmission is not a satisfactory product. It has an annoying "pulsing" feel like it's trying to figure out what gear to use as I'm driving around town. If I get on it it does ok but just cruising around it's very annoying. I've heard lots of reasons for the "problem" and waiting to see if anything can or will be done.

 

I used this too. I used to drive around town in S4. Worked ok but the shift flare into 4th was weird...made it sound like it was shifting into 4th then 5th even through I had it in S4. When on the Freeway I'm in S6 on cruise. If I see a hill, i manually downshift to S5, then S4 depending. I'll hold it lower so it doesn't play the shifting watoosie speedup slowdown routine.

I bought the SS Pro and use that primarily but still find I want 5th gear sooner than it allows and 6th sooner than it allows. The weird shift into 4th seems to be gone...probably because it stays in 3rd longer. Even with the SS Pro I still need to manually tell it what I want at times.

I did think this bit in the PDF on page 40 of 47 is key:

"Artificial Intelligence-shift (AI-shift) Control
1) General The AI-shift control determines optimal transmission control based on input signals and automatically changes the shift pattern. As a result, a high caliber of transmission operation is achieved. The AI-shift control includes a road condition support control and a driver’s intention support control. The AI-shift control is effected only with the shift lever in D, based on the accelerator pedal and brake operation data. The AI-shift control will be canceled when the driver selects the S mode."

I wonder if the Tacoma uses the same approach?

J

 

I honestly think most people floor it when they need power and ride the truck light when they want to cruise. You'd think delivering shiftpoints that accommodate this would result in the best fuel efficiency. Call me crazy.

 

I can't decide if mine is getting better or not, nearing the 1,000 KM mark.
Dealer said they checked the transmission prior to delivery, but couldn't provide any documentation.