LEMON Manuals
: Even more car manuals for everyone: 1960-2025
Home
>>
Subaru
>>
2017
>>
WRX STI
>>
Repair and Diagnosis (Single Page)
>>
Engine Performance
>>
System
>>
Engine Control System (Diagnostics) (P000A To P015B) (2.5L)
>>
Diagnostic Procedure with Diagnostic Trouble Code (DTC)
>>
DTC P0031 A/F/O2 Heater Control Circuit Low Bank 1 Sensor 1
>>
Component Description
April 5, 2026:
LEMON Manuals is launched!
Read the announcement.
Component Description
Fig 1: Front Oxygen (A/F) Sensor Heater Output Voltage Graph
Courtesy of SUBARU OF AMERICA, INC.
Courtesy of SUBARU OF AMERICA, INC.