The TRD edition has this working already from the factory.
Seems all the newer FJ's released after the TRD edition now have it working without the modification.
Also, here's a nice write up
on doing the mod anotherway without cutting the wire in the engine compartment.
Ok, it's been finaly done!
A BIG BIG BIG thanks to Alex H., he did all the study and theory behind it, working with the elec diagrams and logic flow of the FJ's systems - and he doesn't even have an FJ!! . I'm just the lab rat who was crazy enough to try it first. So yes, I now can have both the ATRAC system and the rear locker on at the same time, or just ATRAC, or just rear locker, or none of the above.
Ok, on to how to do it!!.. First off, do this at your own risk, yes this could void your warranty, no don't do it if you have no idea what you are doing, and nobody is responsable if you screw it up or anything else!! But if you want to use the rear locker and ATRAC at the same time, read on!
This is the master cylinder, with the VSC computer on the side of it. For those with service manuals and/or electrical diagrams for the FJ, the large connector with all the wires is A4, the smaller one is A5.
This is the wire you are looking for - it's the SMALL blue/yellow. It's pin 26 on the connector, in the electrical diagrams it's terminal EXI3.
You want to cut the blue/yellow, leaving a good amount of length. You then want to take the connector side of the blue/yellow, and using a T-junction or tap, connect it to the Black/orange wire on connector A5 (pin 1). You do not want to cut the black/orange, just tap into it. The remaining blue/yellow in the wire harness just tie away inside the harness, do not ground it or connect it to anything.
That's it! You now can use ATRAC with the rear locker. Damn that was simple wasn't it?
Ok, the theory behind it (all via Alex). The blue/yellow wire is a signal wire from the rear locker (actualy it's from the dash light circut). When the locker is off, this wire has +12v, telling the VSC computer that the locker is off and it can use ATRAC. When the locker is locked, this wire has 0v, telling the system the locker is locked and then it won't let ATRAC turn on. All we have done is take the wire, and tap it into the 12V acc power on connector A5. This tells the VSC computer that the locker isn't on, all the time, even when the locker is on. This doesn't affect the locker light or any of the other lights or system. It just fools the VSC computer into thinking the locker is off all the time.
In Alex's honor, for all his work on this, I think we should call this the Alex hack!