The check engine light came on my 2008 SR5 4Runner also got a flashing anti skid light, my truck was running fine i found a code reader at Walmart it's a Hyper Tough OBD-II/EOBD cost around $20 US i used it to clear a code telling me my gas cap was not tight i then put some grease on the gas caps O' ring and cleared the codes and check engine light and anti skid flashing light was gone.
What i think is TOYOTO has the check engine light and the flashing anti skid light come on when a gas cap is needing a good twist to get tight/ their trying to send people to their stealer dealers service Dept. where you surly will not just be told to tighten the gas cap, there going to tell you that a full diagnostic check is needed and i am betting when you get the report it will say you need maybe if lucky $800 dollars of work to get you safely back on the street.
Same thing if you go to any Auto Zone for a "free" check engine light code read, can't tell you how many have been sold hundreds of dollars of items not needed by the helpful Auto Zone sales people.