Simon

Johnyrrr, so what your saying is that you took out the reverse light fuse (that was some how backwards?) to cut power to your added reverse lights? I guess Im a little confused.

johnyrrr

Simon. I have a fuse in the power line that goes to the relay that powers my auxillery back up lights. My relay has 4 prongs, a constant + (fused), a neg.-, switched power from existing factory back up lights, and then outgoing power for my auxillery lights.
I took the fuse out of the + lead that feeds the relay. This then left check engine, TRAC/VSC dash lights on and allowed wheel spin at will for a while as described in above posts.

Dozer

Simon, HMMM, as in thats interesting...

When my MAf sensor was dirty one time, the check engine VSC TRAC lights were on etc., the TRAC / VSC became defeated, and I was able to spin freely in 2/4 wd as well which leads me to believe that many scenarios (that put the truck into check engine mode) could occour having the same result ie wheelspin.
When I cleaned the MAF and discod the battery (resetting the computer) it reset and all functions were normal. My theory is that you could disconnect the MAF momentarily, putting the engine into check mode, spin as much as you want, then disco the battery to reset it and carry on you way...however inconvenient, it may get you unstuck. (i havn't had to try it yet)

I know this doesn't solve our problem, which is the ability to switch it on/off from the cab at will, without putting it into check engine mode.

Dozer

johnyrrr

I wonder if there are any long term consiquences of throwing the trucks into check engine situation all the time. Wether it be by my way with the back-up light situation or Dozer's method with the MAF power off method? Dozer I havent looked, but how many wires are coming out of the Maf that would need to be spliced into to make a switch to cycle the thing off. I also think the that maybe you wouldnt always have to pop the batery cable off to reset the check engine situation. in my case the truck fixed itself in around 20 miles or so and about 3 ignition cycles.

aowRS

Thanks for all of the continued enthusiasm surrounding the search for a solution. I've been away from the forum for a week or so and am thrilled that this is still being discussed.

The earlier comment regarding the 2WD 4Runner's TRAC OFF switch still lingers in my mind. Unfortunately I do not have the shop manual that addresses all of the wiring schematics.

In theory, interupting the ABS wiring with a switch would take care of everything - as both TRAC and VSC rely on the ABS system. But that brings in issues of accident liability and the possibility of creating problems with the ABS.

Andreas

Colemanfu

I am in VA now and not FL - so we were in the Mt's yesterday and I was playing on a hill at a friends cabin way out in east bumble (Ekl Creek, VA) . After 2 runs up I had taken off all the grass and the other crap and had dug down to just mud - that thick clay like slick mud. I had it in 4wd and the center diff locked - pushed the button to the left of the dash. I could spin my tires like hell to clean them off - no problems with lights flashing and stupid noises. Both back tires were spinning but only one front? Could my back be locked and the front open in this situation? Looked like the front would spin both but not as the same time.

Only problem was that I started to slide side to side as I lost traction and pinned my drivers side rear one inch from a small tree. If I had went forward or back I was sure to slide & make contact $$$. I did ask the wife to give it a push when I attempted to go forward and that gave me about 3 inches between me and the tree. I got out the ax and cut that stupid tree down and shoved the limbs under my rig. Tree huggers this was private property. I had planned to back down now that the tree was out of the way but she said give it hell when she saw I had a bit more trection going forward! Thats an experienced wheeler, with the new found traction I got a little speed up helping me clean off the ATS's and out I went. I did use another little trick I learned from wheeling with no mud tires and that was to use a stick to clean out the center lugs on the tires a bit. They were caked so thick it looked like slicks. It coudl be luck but I think it gives me one good rotation of traction (or spin the rest of the muck off) and sometimes that's all it takes to get going.

Moral - only do 2 runs (3rd was pushing it), carry recovery tools (had the Hi Lift, ax & hatchet, strap), listen to you spotter.

If I had got super stuck and had to use the HL as a winch ( got to get yourself out befor you take the strap) or had to get the tractor to pull me out I would be shoping for some type of locker right now!

Manfu

Simon

Thats all fine and good Colemanfu, but please don't hi-jack this thread. We want to focus on this problem and we feel like we might be making some headway. Thank You.

4-RUNNIN' FREAK

I remember I posted something about when the VSC and TRAC lights and one more came on. I don't remember exactly what it was, but I will look for it after I post and before I forget what I want to say.
When the lights were on, I was able to spin the wheel all the way down the block (about 1,500 ft) on slightly damp pavement after I put the S/C on.
It was fun

Simon

I was looking at the wireing diagrams that Ducky posted. If you look at page 149 you can see where the switch is for the 2wd trac off switch is. Im not sure where the VSC ECU is but someone else might...

Ducky

Ahh I see it yes.. I think knowing this information well... let me put it this way, i think even if we knew where the VSC ECU was we are gaining enough courage to mess with it... Ill look around for the ECU i thought i saw it somewhere while trying to do the DRL mod... ill check again...

Ducky

I know the vsc relaybox is under the hood... i moved it for my compressor.. ill keep looking...

Duc Hunter

I thought TRAC simply used the ABS to move power "from the wheel that slips to the wheel that grips" left/right at each end. I thought is was required since our trucks do not have traditional limited slip (clutch, viscous or gear) or locking differentials in the front and rear. To me that means, although you hear and feel lots of ABS the TRAC is helping both wheels in the rear and both in front spin, instead of just one-legging it like a traditional open differential would do. It also would not reduce the amount of power you send to the ground, just which wheel is putting it down. That would also explain why it runs even in Low 4WD. I know on my old FJ40 mud was a bitch before the locker, because only one rear and one front would spin. Unless I am missing something I think TRAC, though annoying sounding, should be helping?

Whizkidder

New to this Forum, but I'll take a stab. I have a 2001 Taco, so no TRAC. However, the ABS actuator ECU (co-located with the actuator) gets a signal from the 4WD Low switch (same one tapped into for the "grey wire mod" that fools the E-locker into locking in 2 or 4 wheel high). I don't have ABS, but I'll bet the signal is designed to cut off ABS when an ABS-equipped Taco is in 4WL.

According to the FSM, the switch (on a 2001 Taco) sends a ground signal (all down grey wires) to terminal 18 on the 4WD ECU, terminal 19 of the ECM, terminal 14 of the ABS Actuator/ECU, and to terminal 8 on the E-locker ECU.

I don't have the electrical wiring diagram manual for a vehicle with TRAC, but based on previous posts, I'll bet the same (or a parallel) circuit is used to cut off the TRAC when the center dif is locked.

Should be possible to tap into one or both circuits with DPDT relay and dash switch to disable both without tripping the ECU to throw a CEL code. Without a wiring diagram which includes TRAC, I can't go further. Anyone have the actual TRAC/ABS diagram for aowRS's truck?

wimpywade94

if you want to throw your truck into a check engine mode, just rig a switch up to a 02 sensor to effectivly "turn it off" in otherwords to break continuity, that way you can get unstuck, then click back on, you would still have your check engine light when turned back on till a few starts i imagine but it may work.

wade

Simon

Where might one find an oxygen sensor?

TacomaTRD

I have a 98 Taco TRD w/ ABS. I did the "grey wire mod" to enable the rear locker in 2WD and 4HI. The ABS light does come on when the locker is enabled. I haven't noticed if the ABS is actually disabled or not.

Ducky

Get Yo Own Thread!

Ducky

Ok.. Called the local toyota place up here... more info... (not verified)

p/n starting with 89540 by the firewall drivers side is the VSC ECU

Trac Control Switch (2001 2wd 4runner)

p/n 84988-33030 is $52.88 (Old japanese p/n which is unavailable)
new p/n (switched to American made which of course is more spendy is)
p/n 84988-06010 $66.88

Imma hopefully get to even see where the ECU is to see how much a byotch it will be to open up and see if the pins are there... Im hoping... and praying it might even be the same ECU as the 2wd (which theres a good chance there is) and it is prewired and have wires sitting somewhere in the dash (even less a good chance) lol..

The parts person is like, why do you want that part and to know where the ecu is, are you going to disable it? Im like well yea a bunch of us are trying to, they are like sounds complicated.... lol... it wouldnt be if Toyota didnt make it so.

Whos the person who can get parts here on this board? anyone want to contact them and see if they can get us this part way cheaper?

lee

i stayed home sick from work. in the brief hour or so i was feeling better, i decided to take a drive over to this spot i know to drive around in the dirt and grass. well every time i started to have fun, skidding around, climbing up this little stream... etc... vsc would kick in and end the adventure.

vrooooom... slip (tick tick tick tick tick)... stop. vrooooom... slip (tick tick tick tick tick)... stop.

was the way it went..

Ducky

New New Info =)



From what I was told from another dealer its the part circled in red... sorry for the crappy pic, I had to have him fax it to me... faxes of screenshots suck...

and he said its mostlikely on the passenger kickpanel, not under the hood and not on the drivers side... No clue to confirm this yet, just due to the fact I cant read the damn numbers...

Makes sence I would hate for any ECU to get wet... Notice my Mad L33t Photochopping skilzzz!!