Subaru Legacy BN/BS (2015-2019) Service Manual: Dtc p015a a/f / o2 sensor delayed response - rich to lean bank 1 sensor 1

Subaru Legacy BN/BS (2015-2019) Service Manual / Engine (diagnostics)(h4do) / Diagnostic procedure with diagnostic trouble code (dtc) / Dtc p015a a/f / o2 sensor delayed response - rich to lean bank 1 sensor 1

NOTE:

For the diagnostic procedure, refer to DTC P014C. Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P014C A/F / O2 SENSOR SLOW RESPONSE - RICH TO LEAN BANK 1 SENSOR 1

1. OUTLINE OF DIAGNOSIS

Detect the slow response of front oxygen (A/F) sensor.

For diagnosis, detect the trouble by processing the λ waveform in normal driving without forcibly changing the target air fuel ratio.

2. COMPONENT DESCRIPTION

(A)	Electromotive force	(B)	Air fuel ratio	(C)	Rich
(D)	Lean

(1)	Exhaust gas	(2)	ZrO2

3. EXECUTION CONDITION

Diagnostic method 1 and 2

Secondary Parameters	Execution condition
Battery voltage	> 10.9 V
Closed loop control with main feedback (3000 ms or more)	Operation
Engine speed	≥ 1000 rpm
Intake air amount	≥ 10 g/s (0.35 oz/s)

4. GENERAL DRIVING CYCLE

Perform diagnosis only once in a city driving including normal acceleration and deceleration.

5. DIAGNOSTIC METHOD 1

Detect the malfunction depending on the average value of time necessary for λ to inverse the air fuel ratio from “Lean > Rich > Lean” to “Rich > Lean > Rich”.

Judge as NG when the following conditions are established.

Judgment Value

Malfunction Criteria

Threshold Value

DTC

Average value of time necessary for λ to inverse the air fuel ratio to Lean > Rich > Lean

> 80 ms (CVT model)

> 120 ms (MT model)

P015A

Average value of time necessary for λ to inverse the air fuel ratio to Rich > Lean > Rich

> 200 ms

P015B

Time Needed for Diagnosis: 70000 ms

Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cycles.

6. DIAGNOSTIC METHOD 2

Detect the malfunction by calculating the average amplitude of λ.

Judge as NG when the following conditions are established.

Judgment Value

Malfunction Criteria

Threshold Value

DTC

Average value for λ amplitude

> 0.07 (CVT model)

> 0.09 (MT model)

P015A and P015B

Time Needed for Diagnosis: 70000 ms

Malfunction Indicator Light Illumination: Illuminates when malfunction occurs in 2 continuous driving cycles.

Dtc p015b a/f / o2 sensor delayed response - lean to rich bank 1 sensor 1

NOTE:For the diagnostic procedure, refer to DTC P014C. Diagnostic Procedure with Diagnostic Trouble Code (DTC) > DTC P014C A/F / O2 SENSOR SLOW RESPONSE - RICH TO LEAN BANK 1 SENSOR 11. OUTLINE OF DI ...

Dtc p014d a/f / o2 sensor slow response - lean to rich bank 1 sensor 1

Other materials:

Operation
1. On «Start» display, select «Diagnosis».2. On «Vehicle selection» display, input the target vehicle information and select «Confirmed».3. On «Main Menu» display, select «Each System».4. On «Select System» display, select «Tire Pressure Monitor» and then select «Enter».5. On «Sel ...