Diagnostic Procedure with Cancel Code: 31
WARNING: This page is about a different car, the 2012 Subaru Forester. However, it is still accessible from the selected car via links, so may be relevant.
Engine speed signal malfunction is detected.
Abnormal increase of engine speed is detected.
Gear is placed in 1st or Reverse position.
After driving at the 2nd gear position or higher, perform the cruise setting again. If a cancel code is not detected, it is normal.