ATRAC Hack- Switch on/off

[benc]

The ATRAC is pretty sensitive so I would think it would be quite simple to trick the system into thinking there is a problem.
I may have to play around with it a bit.
I just had a customer with the part time kit ask me if I knew of anything as he would like to play around in the snow.

 

[coveboy]

I'm unsure if the wheel sensors are similar to the system in the Tundra, but I had a stick severe the wire going to mine on my Tundra and it caused my truck to go in a sort of "safety" mode where I couldn't shift out of 4low. But while this wire was still cut, all my nannies seemed to be turned off. The dash lit up like a Christmas tree, but besides being stuck in 4low there seemed to be no problems. Luckily we have true transfer-case shifters in the 100 series so maybe that wouldn't be a problem. Once I spliced the wire back together everything went back to normal.

 

[2001LC]

If I remember right the ATRAC will not work with a malfunctioning wheel sensor,
Could one wire a switch into a wheel sensor to disengage the ATRAC?
Not sure what kind of wire or signal is on the sensor so may not be possible.

Brakes work fine, but ABS shut down is what I've seen.

I've had a hard time refraining from pumping brakes on snow & ice, old habit. So when I found ABS shut down due to bad wheel speed sensors, I pondered splicing in a switch on one wheel speed sensors.

I don't like cutting into factory wires. So my thinking was building a jumper to plug into wire block connection. I'll bet Toyota Dealer sells at least the connecting block housing with pig tails that wheel speed sensor plugs into. They may also sell connection block that's on speed sensor, if not, it could be harvested from a broken sensor. The driveside would be closes to a preferred switch location left of steering wheel. The dash lights would clearly alert when ABS switched off.

There may also be a relay that could be tap IDK. But tapping would surely involve cutting factory wire.

Edited: Note the broken wheel speed sensor was on a 98LX which is before Atrac.

 

[2001LC]

A simple test would be to disconnect one wheel speed sensor.

 

[syche]

If you read through the link i posted, it is all there

 

[abuck99]

More relevant info probably will get us there: Andymod™

First post has links to more detail

Andymod™ (Disable TRAC/VSC/ABS) Mod Installed - Toyota 120 Platforms Forum

And then Andymod 2.0
AndyMod 2.0. ABS Remains Active. - YotaTech Forums

 

[DirtDawg]

More relevant info probably will get us there: Andymod™

First post has links to more detail

Andymod™ (Disable TRAC/VSC/ABS) Mod Installed - Toyota 120 Platforms Forum

And then Andymod 2.0
AndyMod 2.0. ABS Remains Active. - YotaTech Forums

Yes, this andymod has transferred across many platforms, 3rd gen 4Rs, 4th gen 4Rs, cooresponding generations of tacomas, FJs, and many more. All those platforms share similar systems as ours.

After studying wire diagrams last night it looks doable.

 

[hewitttech]

I would not recommend monkeying with the sensor wires at all. They are carry a high frequency signal and is a shielded wire. You don't want to insert any sort of impedance in the way of those sorts of signals. I think i might have a better option but am going to have to dig further into TIS and do some more research to confirm. I think it is a much safer option for the 100 that doesn't have the manual switches to do it like the other method i was talking about which is a much better way imho but you gotta do what you gotta do.

I have been doing more projects with micro controllers as of late if it is simple enough price point guestimate would be in the $50-70 range just depending on which disabling method your vehicle would need.

Thinking this would be able to turn it on and off without having to restart the vehicle.
The andy mod looks simple enough and may work well enough as long as none of it sets trouble codes and applies to the newer vehicles. no need for me to look further into one for the 100 if it does.

 

[DirtDawg]

Heres what Ive found so far:

The ATRAC/VSC/ABS disable mod described earlier in this thread should work, I believe this is the original andymod. Our 100 series uses the same pressure sensor in the master assembly, as well as the same wire colors and labels.

The andymod 2.0 that disables ATRAC/VSC while keeping ABS active however does not look like it will transfer over.

Is there any condition in which our vehicles will have ATRAC and VSC disables without ABS? The andymod 2.0 works where it tricks the VSC ECU into thinking the vehicle is in 4WD Low, this disables the nannies without the ABS. Such a condition does not exist on our vehicles.

 

[abuck99]

I would not recommend monkeying with the sensor wires at all. They are carry a high frequency signal and is a shielded wire. You don't want to insert any sort of impedance in the way of those sorts of signals. I think i might have a better option but am going to have to dig further into TIS and do some more research to confirm. I think it is a much safer option for the 100 that doesn't have the manual switches to do it like the other method i was talking about which is a much better way imho but you gotta do what you gotta do.

I have been doing more projects with micro controllers as of late if it is simple enough price point guestimate would be in the $50-70 range just depending on which disabling method your vehicle would need.

Thinking this would be able to turn it on and off without having to restart the vehicle.
The andy mod looks simple enough and may work well enough as long as none of it sets trouble codes and applies to the newer vehicles. no need for me to look further into one for the 100 if it does.

There are at least two viable options to explore:

• Andymod 2.0 which puts a jumper in line to the VSC signal wire and allows you to switch it on/off, and disables VSC and TRAC (ATRAC) but keeps ABS functioning. You still have to cycle the ignition on/ff to reset the system so on/off on the fly his not possible. (linked above)
• Bagel mod- much more involved and gets into adding relays to fool the ECU. (interesting reading and more along the lines of your thought process) AndyMod 2.0. ABS Remains Active. - YotaTech Forums

I'll preface the the pin location numbers and terminal numbers listed are likely different in the 100, but the concept is the same and its simply a process to find the correct ECU terminal and corresponding pin location for the VSC/ATRAC system. My goal was to tap wiring under the dash, avoiding splices under the hood and running wires through the firewall.

 

[2001LC]

I would not recommend monkeying with the sensor wires at all. They are carry a high frequency signal and is a shielded wire. You don't want to insert any sort of impedance in the way of those sorts of signals. I think i might have a better option but am going to have to dig further into TIS and do some more research to confirm. I think it is a much safer option for the 100 that doesn't have the manual switches to do it like the other method i was talking about which is a much better way imho but you gotta do what you gotta do.

I have been doing more projects with micro controllers as of late if it is simple enough price point guestimate would be in the $50-70 range just depending on which disabling method your vehicle would need.

Thinking this would be able to turn it on and off without having to restart the vehicle.
The andy mod looks simple enough and may work well enough as long as none of it sets trouble codes and applies to the newer vehicles. no need for me to look further into one for the 100 if it does.

Didn't consider impedance of wire, but make sense. Well, my ideas off the broad.

 

[od4x4]

Hoping to resurrect this thread but more importantly to see if there has been any further discovery.

A couple of weeks ago I was in the snow in Yosemite and Atrack decided that my method of driving was not appropriate... POS would not let me get enough wheel spin or speed to drive effectively in the powder. I know that mashing the throttle will help in theory, but I like a little more control. I do like the idea of using lockers to fool the sensors, but there are times that even that would not be best....

Has anyone had any more thoughts about this?

 

[od4x4]

Hmm.... nothing huh.

VSC OFF switch install.

I am aware of this, but to be honest I guess maybe I just need more pretty pictures because I was not able to figure this out with 100% confidence and I hate to start cutting and splicing without being pretty sure.

@abuck99 I know you were looking at this.... anything?

 

[Spike555]

I know next to nothing about the ATRAC, but on Land Rovers if you want to turn off the traction control for certain conditions all you have to do is engage lo range, lock the center diff and then shut the engine off, wait 30sec and start it back up, traction control is off but ABS still works.
All of their off road computer programs can be turned off, instructions are in the owners manual.
Mayb e Toyota has something similar?

 

[LostAfrican]

I think you are over complicating this.

To disable VSC only - ground pin
3 on connector A43 (EXI).

To disable VSC and ATRAC - float (no connection) pin 3 in connector A43 (EXI).

See the thread mentioned above for good pix and diagrams.

For my VSC only mod I do not need to restart the engine to re-engage the VSC.

 

[abuck99]

Hmm.... nothing huh.

VSC OFF switch install.

I am aware of this, but to be honest I guess maybe I just need more pretty pictures because I was not able to figure this out with 100% confidence and I hate to start cutting and splicing without being pretty sure.

@abuck99 I know you were looking at this.... anything?

Hey- yeah I looked into it, and didnt implement the hack. I did not want to cut and splice a switch in. If I get into a situation where I need to temporarily defeat atrac (with out selecting low range) I will pull the abs connector up by the driverside fender.

 

[aedgington]

Hmm.... nothing huh.

VSC OFF switch install.

I am aware of this, but to be honest I guess maybe I just need more pretty pictures because I was not able to figure this out with 100% confidence and I hate to start cutting and splicing without being pretty sure.

@abuck99 I know you were looking at this.... anything?

I found the thread a little daunting myself because of the two very different ways it was done, but it's not that hard once you parse the necessities:

1. Cut the A43/#3 sensor wire -- giving you one wire to the ECU, one wire to the detection signal.
2. Add a grounding wire connection.
3. You now have 3 connections: ECU, ground, signal.
4. Wire a switch* in whatever way you want to toggle the ECU between the ground (VSC disabled) and signal (VSC stock operation).
    * A 3-pole SPDT switch will work just fine. You'll need to grab 12v if it's an illuminated switch.

I plan on tackling this today and will probably post back in that original thread with my results.