What would cause the VSC, ABS and Brake warning lights all come on and off intermittently?

I would say you are having an issue with your sensors...

Did you ever get this checked out? I would say COMETGUY61 is correct~!! I'm currently having the same issue!! Thanks Toyota!! By the way, are you sure it wasn't the VSC, ABS, AND CHECK ENGINE LIGHT??

I checked with a code reader and it said there was a foreign object in one of the rear wheels. I took the wheel apart and put it back together without finding anything. When the weather warmed up the problem went away and hasn't returned. I am curious to see if it returns this winter.

This seems to be a common problem with some of these Toyota vehicles -- Corolla, Camry, Matrix, etc. When visiting RepairPal.com, it's usually the 02 sensor and a Rear Wheel sensor, indicatinG debris -- as in your case GuruCQXP! I certainly don't believe this should be happening in my case with only 49k miles. There's actually a TSB out on the MATRIX for this very issue. However, it's for the previous years, right before mine -- Go Figure. That's for P0607 and the 02 sensor is P0138. These lights seem to come on intermittently, after a good rain...seriously!! Toyota had furnished the "P" codes for me when I brought the Matrix in for the last "recall" -- Takata Air Bags.. I really don't drive my vehicle too often anymore, since I purchased 2016. Thank goodness the lights went off on their own, after a good and long refreshing drive -- Somebody up above was looking out for me that day, as I passed the E-check.....otherwise, automatic fail! This vehicle runs absolute fabulous right night and I hate to give it up, but some memories need to be forgotten.