Check Mode Procedure: Description
WARNING: This page is about a different car, the 2005 Toyota 4Runner. However, it is still accessible from the selected car via links, so may be relevant.
Check mode has a higher sensitivity to malfunctions and can detect malfunctions that normal mode cannot detect. Check mode can also detect all the malfunctions that normal mode can detect. In check mode, DTCs are detected with 1 -trip detection logic.