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Home >> Subaru >> 2019 >> WRX Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System (Diagnostics) (Except For STI) (1 Of 4) >> Diagnostic Procedure With Diagnostic Trouble Code (DTC) >> DTC P015A: A/F/O2 Sensor Delayed Response - Rich To Lean Bank 1 Sensor 1 >> Diagnostic Method 2
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Diagnostic Method 2

Detect the malfunction by calculating the average amplitude of λ.

G08540817Courtesy of SUBARU OF AMERICA, INC.

Judge as NG when the following conditions are established.

JUDGMENT VALUE SPECIFICATION

Malfunction Criteria Threshold Value DTC
Average value for λ amplitude > 0.055 (CVT model)> 0.1 (MT model) P015A and P015B

Time needed for diagnosis: 

120 s (CVT model)

90 s (MT model)

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