Reliability of '01-02 VSC/TRAC electronics?

[rocket2267]

I've seen numerous threads about "VSC TRAC ABS lights all came on" or variations of the same.

What is the general consensus about the reliability of the VSC/TRAC electronics system? Is it generally considered reliable? Or is it considered "crap" and is breaking all the time?

I am aware of the VSC killing power at all the wrong times when offroading, or even trying to leave a stop sign in bad weather, and the Andy MOD 2.0 to turn off the doodads. But I have also read that when the center diff is locked, that VSC is disabled, but TRAC is still enabled. How well does TRAC do at stopping a spinning tire with the CDL engaged? Is that functionality considered "reliable"?

Thx.

 

[jgue467]

I've owned my 01 almost 10 years now, zero issues with much of anything beyond the norm (radiator, bushings) but no electronics of any kind have failed in almost 308K miles including the 4wd.

With 4wd and center diff locked both VSC and TRAC are off. I've never experienced the stuff folks write about VSC and TRAC causing issues from a stop or while driving. I have felt the Positive aspects when I've gone just a little too fast down a curvy dirt road, the system settles the rear end down and gains control in a modest manner.

I think those with experiences of "over control" by the VSC/TRAC ECU have some kind of adjustment issue or bad software. Mine just works as intended. Luck perhaps, but I'll take it! 01s are sweet machines. Enjoy your runner. :cowboy:

 

[96RedRunner]

I'm one that bad mouths 01 02 Trac System. bought 01 with bad module 2-17, replaced with used one $300. 13k mi no problems.
I can't get a answer as to why it failed, will it happen again? things like that bug me.
It saved my bacon one time on a unfamiliar exit ramp, the system has it's good points.
I hope I get 10 yrs 100k + mi trouble free like [MENTION=75316]jgue467[/MENTION].

 

[rocket2267]

I'm one that bad mouths 01 02 Trac System. bought 01 with bad module 2-17, replaced with used one $300. 13k mi no problems.
I can't get a answer as to why it failed, will it happen again? things like that bug me.

I could see how that would bug ya. What is "bad module 2-17"? Is that a date? Or is "2-17" a part number?

 

[rocket2267]

I've owned my 01 almost 10 years now, zero issues with much of anything beyond the norm (radiator, bushings) but no electronics of any kind have failed in almost 308K miles including the 4wd.

Sweet!

With 4wd and center diff locked both VSC and TRAC are off. I've never experienced the stuff folks write about VSC and TRAC causing issues from a stop or while driving. I have felt the Positive aspects when I've gone just a little too fast down a curvy dirt road, the system settles the rear end down and gains control in a modest manner.

Can you verify this statement that engaging the CDL disables both VSC and TRAC?

The reason I ask, is that I found two definitive statements that CDL will disable VSC, but leave TRAC enabled...?

I do know this though. With the 4x4 engage (4Hi or Lo) and the center diff. lock (VSC off), Active TRAC engages the ABS on any wheel, ANYTIME it begins to spin.


Manually disabling Active TRAC (traction control) on a '01 4Runner 4x4 - YotaTech Forums

and

-On 4wd's, VSC is disabled when the vehicle is in 4x4 with the center differential locked. TRAC still remains on in this situation. This is the ideal setup for most off road situations, as TRAC helps in most situations by acting as a limited slip differential for all 4 wheels. Situations where it is best to also be without TRAC would include deep sand and mud


https://www.toyota-4runner.org/706219-post3.html

 

[96RedRunner]

I could see how that would bug ya. What is "bad module 2-17"? Is that a date? Or is "2-17" a part number?

Bought 01 Feb 2017 with bad module.

 

[rocket2267]

Bought 01 Feb 2017 with bad module.

Ouch.

Copy. Thx for clarifying.

 

[jgue467]

Sweet!



Can you verify this statement that engaging the CDL disables both VSC and TRAC?

The reason I ask, is that I found two definitive statements that CDL will disable VSC, but leave TRAC enabled...?



and

My bad memory, tried it this am and yes TRAC doesn't turn off. The Andy Mod 2 will take care of that if desired. Thus far I haven't found a need yet I'm sure on extreme 4wheeling it is there (or a rear locker). But we don't get regular snow that sticks in central texas, anymore (gone 2 decades ago), only get lots of rain which gives us good mud situations.

What I can say is this when I offroad besides the usual packed soil, small/med rock, turf/grasses and mud, using proper technique and speed I haven't got stuck other than dumb situations I got myself into (towing a trailer with some weight in sand and stopping, bad idea). Mudding sure it lots of fun with the standard 01 setup, never slows down or stuggles, just puts along smoothly.

For mild to normal offroading, it's adequate as is, Andy Mod could only make it better. Reading thru the official toyota TRAC literature, it says sand and mud are situations where they suggest TRAC being off.

Everyone has their opinions on VSC and TRAC, most don't like this generation's version, say it's too early a version and ineffective causing engine power to be cut too much, I've never had that happen, not a large power cut, just very mild one, almost none detectable to me anyway.

I'd say find one to drive and find out. Luck and enjoy. :cowboy:

 

[rocket2267]

[MENTION=75316]jgue467[/MENTION], thanks for confirming that for me!

 

[rocket2267]

There is something apparently called the Beto mod -- a take off on the Andy MOD 2.0. If I understand correctly, the Beto mod will enable you to turn VSC off, but keep TRAC on. Perhaps there's a time you want to run the center diff unlocked, but still want TRAC to stop wheel spin. FWIW.

This TacomaWorld thread, OEM+ Overlander, where a fellow swapped a torsen, locking center diff transfer case from a 4th gen runner into his 2nd gen taco, got me thinking about doing the same with my '04 taco DCSB. I'm pretty sure the locking center diff t-case from a '99-00 limited or '01-02 4runner will go in my taco, as they both use the A340F tranny (although I have not confirmed that just yet). But part two is whether the VSC/TRAC from an '01-02 runner could be swapped in, and what is involved. If TRAC stops wheelspin on just the affected wheel, and VSC can be turned off (either CDL or Beto mod), then front and rear TrueTracs might make for an interesting traction seeking beast.

But if the VSC/TRAC electronics are problem plagued children, then that part of the equation may not be worth the headache.

 

[phattyduck]

But if the VSC/TRAC electronics are problem plagued children, then that part of the equation may not be worth the headache.

The '01/'02 VSC/TRAC system is not just the electronics - it is a hydro-electric master cylinder and ABS unit combined, along with 4-channel (instead of the previous 3-channel) ABS. New brake lines, completely different ABS/master cylinder setup, etc.

I'm sure it could be done with a complete donor vehicle to pull parts off of... but what would it get you?

A multi-mode transfer case swap (with its separate computer) and true-tracs F/R would get you most of the way there, without completely re-wiring and re-plumbing your truck...

I personally have dreams of the FJ Cruiser MT transfer case (full-time 4WD with Torsen center diff, mechanically operated), but I think the spline count is wrong for the A340 output shaft...

-Charlie

 

[rocket2267]

The '01/'02 VSC/TRAC system is not just the electronics - it is a hydro-electric master cylinder and ABS unit combined, along with 4-channel (instead of the previous 3-channel) ABS. New brake lines, completely different ABS/master cylinder setup, etc.

Right. Not a walk in the park, but potentially doable. PITA factor may be off the chart, though.

I'm sure it could be done with a complete donor vehicle to pull parts off of... but what would it get you?

TRAC. To stop wheel spin if / when a tire get's lifted -- more efficient than applying brakes by foot or e-brake as the non-lifted tire will not have to overcome the brake force as well. Also, one less thing to have to think about.

VSC. On slicker than snot roads, VSC to keep rear end from going ass over tea kettle around turns. Beto mod to optionally disable VSC when you don't want it getting in the way.

A multi-mode transfer case swap (with its separate computer) and true-tracs F/R would get you most of the way there, without completely re-wiring and re-plumbing your truck...

I agree. I may do just that and call it good. OR, I may swap in a multi-mode t-case, but leave my e-locker in the back of my Taco to avoid losing the rear end in dicey situations. But in 4WD unlocked (aka AWD) would benefit from TrueTrac in the front for traction. Maybe this is my best choice.

I personally have dreams of the FJ Cruiser MT transfer case (full-time 4WD with Torsen center diff, mechanically operated), but I think the spline count is wrong for the A340 output shaft...

A full-time 4WD mechanically operated Torsen center diff would be sweet! Alas, I think you are correct about not mating up with the A340 without 'spensive surgery.

Thanks, Charlie!

 

[phattyduck]

Oh, another thought... the VSC/TRAC system is also integrated into engine control - the '01/'02's had a DBW (ish) system that could reduce engine power as needed as part of the system. Which then requires the '01/'02 trans (solenoid controlled line pressure instead of cable operated)... it was a pretty extensive change.

-Charlie

 

[rocket2267]

Thread copy / rename / deletion of original thread

FYI -- I copied the old thread to this thread to rename it to reflect the fact that VSC/TRAC was only available on '01-02 3rd gen T4Rs. If you had subscribed to the old thread, you may need to re-subscribe to this thread, if you wish to be subscribed, that is.