I wouldn't jump to the conclusion of it being the fuel just yet. Personally I would recommend you get it read because it could seriously be anything and it would be helpful to know. When I had my light come on, I had filled up my fuel not too long before it and thought that could have been the cause. Turned out mine was a true ABS/VSC error. Toyota (or an OBDII scan gauge) can tell you the error code that can let you know where the problem could have come from. Otherwise, yep, just pull your negative terminal off, leave it for a few minutes (even 10 to be sure) then connect it back up. If you start the engine and the error does not come up immediately, then it's nothing major. If your drive and reach about 60km/h and it comes back, I'd really suggest to get the code read.