Who can explain the "Power ETC" button to me?

http://www.bing.com/images/search?q...a76fd2282baab326308fb35531511596H0&ajaxhist=0

 

You joined the forum less than a year ago and talk like your some Tacoma Authority.. ha! Now I know your not a credible source of information. Thank you for clarifying that.

btw..

 

so joining a month ago makes a jackass smarter?

 

Probably not technical enough response? You will probably count the days for more accuracy

 

False. There are provably unbreakable encryption schemes. They wouldn't be much use in locking down ECU code, but they do exist.

https://en.wikipedia.org/wiki/One-time_pad

encrypting an ECU to the extent that the payoff isn't worth the effort to break it isn't technically difficult, but it does require more effort up front, and more expensive chips to accomplish. So it boils down to how big a priority it was for Toyota and how much they wanted to spend. I can see a few reasons (liability, warranty costs) that would drive a "lock it down" decision.

It's an inherently mathematical topic, but if anyone has an interest in general encryption, Bruce Schneier's "Applied Cryptography" is fairly accessible to a layman, although some exposure to higher math helps.

 

Okay, so you found the one system that's only as good as its writer.... I studied this back in school, its actually simple once you break down the process. Due to the potential for human error, I would call this method 99.8% secure. Thank you for the trip down memory lane.

 

invites @tacitos to a thread about suspensions or tires

 

I agree with this...I used the switch today, you can really feel the difference. I wish I knew a way for it to automatically be on Vs. turning it on every time. It's as if the Engineers said "this is how the truck should run, but we we really needed to hit some EPA goals"

 

I'm assuming that you were actually trying to reply to my post?

A one time pad is not "as good as it's writer", it's as good as the random number generator is and as good as the key distribution method is. As I said, it's not useful for ECU encryption, but it is provably secure when done right. And yes, it is simple, which is one of the beauties of it.

My larger point is that it's completely possible that Toyota made hacking the ECU too difficult to be worthwhile. Not hard, it just takes the commitment of some resources.

It also worth pointing out that a good, practical, encryption scheme doesn't rely on being clever, and isn't susceptible to "cleverness" as a means of attack. It's only vulnerable to brute force attacks, and the goal to make the cost of such an attack more expensive than the information would be worth.

 

My old 2001 4 runner had this power etc button. So the new 16 tacoma's now have this?

 

I have a programmable relay on the way to see if I can do exactly this. If you took notice, it's not just the transmission shift points that have changed. It takes much less throttle to get the truck off the line.

Yes. The difference in your 4Runner is that it only controls the transmission and it is latchable, meaning it will retain it's setting from one drive cycle to the next. In the 2016 Tacoma, this is not the case. However the ECT mode, which is more of a 'sport' mode, controls various powertrain settings to improve the responsiveness of the truck.

 

Is it possible the ECT button has some influence on the VVTi cam sprockets? From what I understand during cruising speeds the VVTi cam sprocket will adjust itself to a low lift / low duration setting, and during hard acceleration it will adjust to high lift / high duration cam setting.

Based on what people are experiencing on here it sounds like there could be some correlation between the ECT and VVTi.. am I wrong?

 

If the VVTi is electronically controlled then it's possible. If it's a mechanical control then it would be very unlikely.
If I had to bet I would think that it just controls throttle mapping and shift points. Just a guess though.

 

VVTi uses an electronic actuator that control the flow of pressurized oil to and from the cam. So I'm sure its electronic and controlled through the ECU.

I agree it has some control of the mapping or shift points, but the mystery remains if the ECT has any direct / indirect influence on VVTi.

 

I don't think it affect the VVTi, I think that runs at max efficiency at all times; makes no sense to change this.

I'm guessing the ECT button adjusts the bias between the Otto and Atkinson cycle. I may be wrong, but I have a feeling that with ECT Normal engaged, the ECU is more bias towards Atkinson cycle running, even when accelerating. With ECT On, the engine probably runs 100% on Otto cycle except at cruise.

 

I agree with what your saying, but isn't the VVTi what actually controls the switch between Otto and Atkinson?

 

I read through a couple pages of responses to the question and just died laughing! Some of these replies are just hilarious.....

 

VVTi is what makes this possible. But I don't think the ECT Button changes intake/exhaust valve timing to increase power or anything like that. And to be clear, the ECT doesn't really do anything. The ECU is what controls everything (including your trans shift points), ECT just sends a signal to the ECU to change bias's, etc...

 

The ECT button does tell the ECU what the driver is demanding.. then the ECU adjusts settings for more power, adjusting VVTi to switch to Otto, Fuel map, shift points etc... No?

 

In the first gen it just changes shift points.

I'm guessing it does three things in the 2016:

-Changes shift points definitely.

-The ECT button probably changes how the ECU reacts to the gas pedal for better response to pedal input. Some manufactures delay reaction to depression of the gas pedal to insure acceleration is smooth, and more importantly burns as little gas as possible. This results in a feeling of sluggishness of the line and a delayed "punch" when you go heavy on the gas.

-I'm guessing it adjusts the bias between running in Otto and Atkinson cycle. I have no evidence to support this and can't talk about it intelligibly as Toyota hasn't been forthcoming on how the ECU controls Otto and Atkinson cycle running.