DTC Detecting Condition:

WARNING: This page is about a different car, the 2004 Subaru Impreza. However, it is still accessible from the selected car via links, so may be relevant.

Two consecutive driving cycles with fault
GENERAL DESCRIPTION < Ref. to DTC P0463 -- FUEL LEVEL SENSOR CIRCUIT HIGH INPUT , Diagnostic Trouble Code (DTC) Detecting Criteria.>

CAUTION: After repair or replacement of faulty parts, conduct Clear Memory Mode < Ref. to OPERATION .> and Inspection Mode < Ref. to OPERATION .>.