Subaru 2009 IMPREZA Service Manual page 1707

Diagnostic Trouble Code (DTC) Detecting Criteria
When B < C (solenoid OFF)
(b)
(a) Barometric pressure
(1) Valve
When Solenoid is ON
(b)
(a) Barometric pressure
B
(b) Fuel tank
B
(b) Fuel tank
GD(H4DOTC)-119
A
(a)
C
(1)
(c) Canister
A
(a)
C
(c) Canister
GENERAL DESCRIPTION
(c)
EN-01718
(c)
EN-01719