Mod- built a shift-controller for Gen3 auto transmission S-mode using microcontroller

What if you're in ECT mode and S mode. Does your system over ride the stock ECT shift points?

 

OP, you said that after the TSB the shifting felt better and then went to its normal settings which you did not like. Was the shifting behavior immediately after the TSB still off from what you want as permanent?

I think most know that after the TSB or any other reset of the ECM the transmission has no accumulated data for calculating the "learned" shift pattern. Otherwise known as AI, auto-intelligence. Gradually data is gathered and new shift points are established. Some like yourself don't like these shift points. I believe you can achieve the same shift behavior as immediately experienced after an ECM any time by driving in S6 as from what I have read using S mode disables AI. Did you gather any comparative data just driving in S6 in the same way you would drive in D?

 

@DoorDing would be so proud.

 

Being the nerd I am I just had to look this up and it looks like the answer to my question is yes!



W-B is a simple ground switch, and SFTD and SFTU look like the "Upshift/Downshift" actuators. Yellow and Pink are more complex, tied into the PRNDS stuff. Looks like the connector terminal itself is right in the center console, pop the shift boot down, take off the shift knob, pull up on the console and you will have access to switching the blue and red wire in the terminal.

It's cold as shit in the garage though and I don't feel like going out there to mess with it.

 

i recognize this diagram well! and yes, this is the 5 wire connector on the left side of the shift lever. this is where i interface with the microcontroller. P,N,D is a different connector.

 

Mike Sweers was a lying sack of shit back then. I'm glad someone was able to correct something that him and his "engineers" dropped the ball on. I understand that you have to maximize MPG for litigational reasons, but at least give the consumer a chance to make the choice what he chooses to do with their fuel economy themselves.

Great job OP. You have become the hero of the 3rd gen forums.

 

Just wondering, where did you get the wiring diagram from?

 

Sub'd

 

a 2-day access to the toyota TiS system.

 

They did give you a choice, 1st choice is a manual trans, 2nd choice if you chose the auto is the s mode. The OP, just automated the s mode.

 

^Like this. The other choice is to push the right pedal further. If you look at the OP charts you can see the more throttle the later the shift. I have no issue with the A/T, but I probably use more throttle than most. You really have three modes and in my opinion have a lot of control over how the A/T operates. D, ECT, and S modes. This is not meant to take anything away from what the OP has put together it is great. I just have no need for it. It would be cool to see what my down loads look like compared to his. I just did a ECU reset to see how the learning process will go now that I have 2K miles on it and I no longer baby it at all.

 

So the obvious question.....


Why can't the wizards at Toyota give us an update that actually works decent???

I've had 2 updates that marginally work at best...(they suck)

Sounds like David is slaying Goliath here.

 

Because it will kill gas milage.

Then a class action lawsuit will happen.

It's easier to just keep making the best selling mid sized truck than to make a major ECU revision that'll kill gas milage because a few people bitch about it.

 

If you try to accelerate at too low an rpm you will get worse mileage. Same with holding gears too long up a hill. Over my ~5k miles with my '17, SGII, and the ECO app I can tell you the transmission does not always choose the most efficient gear. Why not? I don't know; maybe, because everyone is complaining about too much shifting?

The cruise on my 17 will allow more throttle before downshifting than you can give without it. (This is the reverse of my '02.) This gives lower mpg and can result in a second downshift that may not have happened without cruise. Then it holds the lower gear longer than it should, also reducing mpg.

While accelerating, when mine hits 4th and almost immediately locks ups the converter it reduces rpm too much for that amount of throttle... again reducing mpg. Why? I don't know.

...and ECT revs too high for best MPG.

 

you might just be able to make your taco fly with that!

 

These are awesome!!

 

I don't like the aggressiveness of the ECT either but an update that leans more in that direction, one that revs just a bit higher and doesn't shift into 5th-6th at 40 mph would be a major improvement.

 

OP.. Call me old but I really enjoy driving with the CC on. Would this mod enhance the driving experience with the CC enabled? I can drive a 10 mile loop without the CC enabled and never see 4 gear while maintaining 70mph. Enable the CC on the same route/speed and it will spend 45 seconds in 4th.

 

I have an Ms I mechanical too with a concentration in mechatronics. Though, in practice now I do machine design.

What language/how did you program this?
This is very cool but in my more school experience I wouldn't be able to do this without pulling data out real time and processing with matlab/SQL



Edit: you did it with an arduino... I guess I should have read the whole thread before asking

 

Nice idea OP ! Glad it's working for you. Personally I wouldn't tweak my Tacoma's electronics . But then I'm not a engineer, I'm just an electrician by trade . I have no problems whatsoever with my 16' ! Am I the lucky one or is it because I drive with 2 feet and always have my right foot on the gas pedal and brake with my left, been driving that way for 44 years. Quote from the movie Avatar "I feel you" that's how I drive.