I had this problem several days ago. VSC TRAC and VSC lights lit up on the dash. No Check Engine Light and no ABS Light. I tested the ABS on some ice and it did kick in. So ABS and VSC are infact seperate.

I researched this problem on this forum. 2 situations that can possibly result in this condition both were done to my 2003 4runner.

1) the toyota ODBII scanner was attached to it
2) a new key was programmed for the truck. But not sure how they program a new key, maybe it is also with the ODBII??

Anyhow many persons have listed the above as causing this issue to manifest itself. Brought it back to toyota, and they preformed the Zero Point Calibration on it. This has fixed my problem. It's been several days and it hasn't come back. I tried resetting this with 2 other ODBII belonging to a mechanic I know but was not able to perform the recalibration. So be advised if you plan on buying a ODBII scanner for only this particular problem, the non toyota scanners might not have the capability....the BR001-4 provideds information on how to reset manually with the scanner.