Traction Control - Everything You Want to Know

I think I'd have to be in the truck to really understand the scenario. Do you mean one tire seems to be slipping while you're turning, or the truck doesn't seem to be moving with as much thrust as you think it should? Does the light flash on the dash?

 

I have been wheeling by myself so I could learn and not have to depend on someone but I was also prepared, this is great info! I never encountered a situation where I would need a locker but then again it wasn’t “extreme”, 4low works great and if some of the technology mentioned here were used properly you would think our tundras have crawl control (the step child of Toyota that does not have it yet).

 

are you lifted at all? if so you may have to do the VSC mode/calibration...when you take away the trucks rake(nose low) it messes with that sensor and the truck will cut power and shift weird...

https://www.youtube.com/watch?v=fyj9gvxysL8

 

Nope. No lifted. Totally stock. All 3 Tundras I've had have done this. It doesn't do it when I have the Auto LSD light on. I'm guessing it's something with the angle of the truck.

 

beyond my pay grade lol

 

Awesome writeup!

 

KevinK,
Your first post in this discussion states:

"ATRAC - Or A-TRAC, this is Toyota's Active Traction Control. It applies the brakes to stop a spinning wheel. Can also retard engine timing to reduce power applied to the driveline (to prevent breakage of driveline parts). When loss of traction is detected the wheel slip light flashes and you’ll hear ticking noises until traction is returned. ATRAC is defaulted to "ON" when the truck is started in any drive mode (2WD, 4HI, 4LO)."

The manual for my 2017 Tundra 5.7L 4WD (page 235) states that TRAC is for 2WD only. A-TRAC is for 4WD when you switch to that mode. TRAC mode does not apply when in 4 wheel drive. Is the only difference between TRAC and A-TRAC the control provided when in 2WD or 4WD? Is there a difference in the way engine power is reduced?

 

Hey Kevin... how you liking the snow?

My question is the power range... is it 1800-2200 or 1500-2000? This makes a world of difference on my gas mileage and you know us AZTG folks are really anal about the gas mileage.

 

Good catch Clay - the terms TRAC and ATRAC are essentially synonymous. You are correct that TRAC is the 2wd version and ATRAC is the 4wd version. As far as I've been able to see, there is no difference in how they function, other than including the front wheels in the process for 4wd (I think that's why they added "Active" to the 4wd version).

I'm going to update the OP to try and clarify this a little

The snow is fun! press the VSC Off button once to engage the Auto LSD mode and it won't pull power form you when one tire hits a bit of snow while the other has traction.
Now, stopping a 6500 lb projectile is interesting...


LoL at the power range. It is the higher range, and will certainly impact your mpg for the 1.7 seconds that it's active.

 

thanks for taking the time to gather all of this in one place. well done!

 

Kevin,
I'm sure this Control mess changes with each generation of Tundra. All this discombobulation is disconcerting for my one Trac mind.
It would really be interesting to talk to the Toyota software programmer responsible for controls to see the fine details of what happens in all the different drive configurations.
Thanks!
Clay

LSD
Dictionary result for LSD
/ˌel ˌes ˈdē/
noun

1. a synthetic crystalline compound, lysergic acid diethylamide, that is a potent hallucinogenic drug.

 

LSD is almost certainly a contributing factor.

Yeah, the programming of things is updated pretty regularly. Or at least at generational changes. We've seen some possible disparity between 2013 and 2014+ ABS programming. I'd love to see a release notes doc from Toyota, but not sure how to even go about finding one. The people I've asked don't know of the existence of one.

 

Kevin,

For me, all the verbiage is hard to retain when trying to understand the overall Nanny control scheme. I created the attached table to get a better picture. Please review and see if the table is correct. Thanks.

 

Hey Jim - this looks correct and is an awesome way to illustrate the modes!

I'm going to add it to the original post for reference.

 

Kevin,
Attached is the PDF file for the Nanny Control table.
Hope this helps clarify the Nanny Control scheme.
Eschew Obfuscation,
Jim

 

Have you read my bible? The Old Testament is also identified in the black circle.

 

Things are more like they used to be than they are now.

 

Kevin,

This table brings up an interesting observation. My 2017 Tundra owners manual, page 233, defines the Swerving Car Off button on the dash as the "VSC off switch". This description is only accurate when the first 3 second push is done in 2wd or 4wd HI mode. At other times, it is a "TRAC / A-TRAC off switch". Perhaps Toyota should label it as a "Nanny Control switch" or the "Nuanced Nanny Nullifier switch". The Toyota manual description name has been confusing to me, but this table helps clarify what's going on.

Eschew Obfuscation,
Jim

 

The manual I had used for the original post was from a second gen, but I drive a third gen, and I think they're different.

Obfuscate eschewed obfuscation

 

WOW. The only reference to EBD, Electronic Brake Distribution, I found was in a Tundra 2017 Quick Reference Guide. It isn't mentioned in the Tundra 2017 Owners Manual or the Tundra 2017 Warranty and Maintenance Guides, FFV or Regular engines.

Are there separate buttons for Nanny control for the Gen 2, or only one button like on the Gen 3? There is no VSC in 4wd on your chart. And the 1st 3 second hold mode on the Gen 3 table seems to be missing. I can understand if the Gen 3 requires an extra 3 second hold if there is only one Nanny Control button.

Interesting.

 

I think there’s only one button also on the 2nd gen as in the 3rd but there’s some difference in the 3 second hold I believe. I linked the manual pages in the OP of this thread. I should grab my 2014 manual and check it against this.

 

I would expect your 2014 Manual would be the same as my 2017 Manual. But maybe not. My 2017 Manual does not have a table similar to the one you posted. I guess Toyota feels that confusing verbiage is enough.

 

I'm not even sure where that table came from. A product of internet efficiency I'm sure (I probably copied it form another post someplace). My 2014 manual doesn't have that table, and I just checked a 2013 manual - it also does not have it.

I think the cheat sheet you made is the best one.

 

Awesome write up! I will definitely be saving this thread.

 

Mine is easier to comprehend, at least for me since it came from my one Trac mind. It's easy to see Toyota's logic when you look at the structure from the table. I was surprised to see how the Nanny control scheme flowed once the table was built. But I couldn't have made the table without your explanations. I certainly wouldn't have gotten it by briefly reading the manual. Thanks Kevin!

 

alpinepro4, I've already copied the table and put it in my Owner's Manual. Will probably put a copy in the truck too.
Kevin say's it accurate, so it must be close to the truth.

 

I just found this table on T4R.org.



Yet another Toyota flavor.

 

Kevin's chart is for a Tacoma, at this address:

https://www.tacomaworld.com/threads...rols-trac-auto-lsd-a-trac-rear-locker.212057/




Check out that web site, the dash board controls are totally different from my Tundra. The post is from 2012.

 

Awesome post... thank you

 

Fantastic write up KevinK!