yabedude

More info (page 05-312) ...

It seems that if I had a 'hand held tester' I could plug it into DLC3 and run 'active test', 4 of which do the following:

ITEM Vehicle condition/Test details
----------- ----------------------------------------------
SRCF (SA1) Turns TRAC solenoid SRCF (SA1) ON/OFF
SRCR (SA2) Turns TRAC solenoid SRCR (SA2) ON/OFF
SRMF (SMCF, SA3) Turns TRAC solenoid SRMF (SMCF, SA3) ON/OFF
SRMR (SMCR, SA4) Turns TRAC solenoid SRMR (SMCR, SA4) ON/OFF

All 4 tests cause the operation of solenoid (clicking sound) can be heard.

I'm guessing that the last character in each item is Rear or Front.
Reading other pages tends to indicate that SRC, SPC, SRC, and STR are directly related to the brake master cylinder which seems to jive with whatever occured in the test that Andreas performed.

DAMN! There is a TRAC OFF BUTTON TO THE RIGHT OF THE CENTER DIFF BUTTON in this manual!!!

I started using my head about links and decided to use my old web server that lies idle ...

2003 TRAC details are in the following PDF which was extracted from the 2003 repair manuals:
http://www.synertech.com/chris/2003_...iagnostics.pdf

I think a call to the dealer is in order ... hopefully to place an order for a TRAC OFF button!

aowRS

Very interesting Chris. I just do not understand why Toyota would equip some vehicles (3rd Gen & 4th Gen) with this switch, and not others. That seems to add validity to an earlier comment that ECUs and such may in fact be the same between 2WD and 4WD models.

The search goes on.

Andreas

Parsh

I pulled the switch covers out on mine today and there are two wiring connectors in there, one black and one blue. I don't have any books, so I can't tell you what they are for, or if anything else besides a switch is missing to activate them.

mypalthetortoise

There is a TRAC switch for the 4th gen. P/N 84988-35040 I think.

AdemaDude1960

I have an 04 Sequoia and i tried pulling the sensor while the truck was on and i did lose the PITA VSC/TRAC but i had next to no braking what so ever. I was moving at about 10 mph and it took a good 20 feet to stop and keep in mind i had the brake to the floor. I almost got a way of wiring a switch which will disengage the relay for the TRAC/VSC but keep the ABS completely. Strangley enough, i had to pull the 4wd fuse, start the engine, flip my switch which disengaged the VSC/TRAC, turn it off and put the fuse back in after it started it again and it seemed to work. Not sure if i messed anything up or not. I went wheeling yesterday and i have never slung mud that far in the beast. I didn't get any abs noise what so ever. Can anyone explain why this worked?


Brendon

aowRS

How on earth did you figure that flow chart out??

No idea why it works the way you describe though.

Andreas

aowRS

Brendon,
This is from a member of 4X4Wire regarding the same issue:

"On my wifes Sequoia I unplugged a sensor on the brake master cylinder. This disabled the VSC and traction control but the ABS functions normally. On the Sequoia it was the sensor farthest forward and on the bottom of the master cylinder."

Andreas

Simon

I can say for sure that ABS doesn't work with "Andymod"

aowRS

Simon,
Sounds good. By that I assume you pulled the pressure sensor connector?

I think the name "AndyMod" will only have validity when we figure out which of the three sensor wires to interupt with a switch. Until then, it's just backwoods shadetree mechanics...

That is, unless Mr. Ducksworth figures out how and where to plug the factory TRAC OFF switch that I would like to reimburse him for....

Andreas

lee

seriously, what a jerk. get on it.

aowRS

Lee,
Any donuts yet?

Andreas

lee

YUP!

worked like a charm. didnt even realize my runner was capable of such freedom.

i overdid actually and skidded kind of scarily at one point, but all is well.

mikNtx

scans of the center diff lock diagnostic circuit "di" are uploaded at:

http://community.webshots.com/album/254318478jhyxPZ

aowRS

Thanks Mike!

Andreas

AdemaDude1960

Hey i went 4wheeling tonight in my sequoia after i finished wiring it completely and i was able to flip the switch without having to pull the 4wd fuse. I have never had so much fun in that thing...My buddy has an 03 TRD Tacoma 4X4 and i was pulling better figure 8's and donuts then he was. I also was having more wheelspin as well. I was pulling so many dounuts that i pulled to sharp of a donut and the tire broke the bead and came of the rim...the new beadlock rims and 35X12.50's will fix that after i put the dana 44 in the back and re-gear the front. If any of you would like me to send you directions on how i wired it, i took pics and i will send them to you via e-mail with all the parts and directions on how i did it. I am not sure if it will work on the 4 runners but it's working perfectly on my sequoia. BTW, the way i figured out the flow chart was went on e-bay and bought the manual(the 678page one ) and compared it to the charts you guys set up, as well as wiring diagrams i found on the VSC/TRAC system and just did guess and check methods till i found one that worked. If any one wants any video footage of me and the Taco 4wheeling just tell me and i will e-mail you the video as proof that my system i rigged up worked....Later guys,

Brendon

aowRS

We want to see and know E V E R Y T H I N G!!!!!!!



Andreas

yabedude

Hi Brendon,

I can feel the glee in your post about being able to disable TRAC in your Sequoia. I'd be interested in your pics, movies, and anything else you have on the subject. With your permission, I could also store them on my web server and post them to the VSC/TRAC thread for others to enjoy.

Either way, could you please email me the files? PM sent.

aowRS

Hope ol' Brendon isn't pulling a few legs with that kind of info?!?!

Andreas

lee

yes, id also offer up some webspace for your materials!!

dlbrunner

I may be a little out of turn here, but all this discussion seems to be focused around getting the wheels to spin. If the trac/vsc systems use the master and brake cylinders to control wheel rotation, then it seems logical the ABS would be tied in with this, and would be affected by any modifications to the VSC/TRAC systems. This banter is great though. Seems like the best solution might be along the lines of disabling the thing completely. Considering the trucks in question all have slush boxes, ABS would be a good thing on steep creepy hill descents

IMO ABS is bad off road, I got a little surprise in my company truck a while back, sometimes while driving on dirt I go a little fast and slide through corners. Imagine my surprise when the little blazer I was driving didn't slide, kept going straight, I did something quick and barely missed a cactus. Evil ABS...... make butt pucker!
This makes me think I may want to be able to disconnect the ABS on my 2nd gen for situations where I want to slide.
Good luck and GREAT work