Subaru 2009 IMPREZA Service Manual page 769

Diagnostic Trouble Code (DTC) Detecting Criteria
AB:DTC P0131 O2 SENSOR CIRCUIT LOW VOLTAGE (BANK 1 SENSOR 1)
1. OUTLINE OF DIAGNOSIS
Detect the open or short circuit of sensor.
Judge as NG, when the element voltage is out of the specified range.
2. COMPONENT DESCRIPTION
(2)
(4)
(A) Electromotive force
(D) Rich
(1) Atmosphere
(2) Exhaust gas
3. ENABLE CONDITIONS
Secondary Parameters
Battery voltage
4. GENERAL DRIVING CYCLE
Always perform the diagnosis continuously.
(3)
(1)
(2)
(B) Air fuel ratio
(3) ZrO
2
Enable Condition
10.9 V
GD(H4SO)-45
(A)
(C)
(C) Lean
(4) Ceramic heater
GENERAL DESCRIPTION
(B) (D)
EN-01693