Subaru 2009 IMPREZA Service Manual page 1730

Diagnostic Trouble Code (DTC) Detecting Criteria
GENERAL DESCRIPTION
BU:DTC P0459 EVAPORATIVE EMISSION SYSTEM PURGE CONTROL VALVE
CIRCUIT HIGH
1. OUTLINE OF DIAGNOSIS
Detect open or short circuit of the purge control solenoid valve.
Judge as NG when the ECM output level differs from the actual terminal level.
2. COMPONENT DESCRIPTION
(A) To canister
3. ENABLE CONDITION
Secondary Parameters
Battery voltage
Elapsed time after starting the engine
4. GENERAL DRIVING CYCLE
Always perform the diagnosis after starting the engine.
(B) (A)
(B) To intake manifold
Enable Conditions
10.9 V
1 second
GD(H4DOTC)-142
EN-02197