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Home >> Subaru >> 2019 >> WRX Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostics) (Except For STI) (4 Of 4) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P2271: O2 Sensor Signal Biased/Stuck Rich Bank 1 Sensor 2 >> Diagnostic Method
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Diagnostic Method

If the duration of time while the following conditions are met is longer than the time indicated, judge as NG.

JUDGMENT VALUE SPECIFICATION

Malfunction Criteria Threshold Value
Output voltage of rear oxygen sensor > 0.15 V

Time needed for diagnosis:  0.5 seconds

Malfunction indicator light illumination:  Illuminates when malfunction occurs in 2 continuous driving cycles.