Nissan Versa

 Sedan Service Manual

Engine » Engine control system (EC) » P0131 A/F sensor 1
DTC Logic

DTC DETECTION LOGIC

To judge the malfunction, the diagnosis checks that the A/F signal computed by ECM from the A/F sensor 1 signal is not inordinately low.

DTC No.	Trouble diagnosis name	DTC detecting condition	Possible cause
P0131	Air fuel ratio (A/F) sensor 1 circuit low voltage	The A/F signal computed by ECM from the A/F sensor 1 signal is constantly approx. 0 V.	Harness or connectors (The A/F sensor 1 circuit is open or shorted.) A/F sensor 1

DTC CONFIRMATION PROCEDURE

1.PRECONDITIONING

If DTC Confirmation Procedure has been previously conducted, always perform the following procedure before conducting the next test.

1. Turn ignition switch OFF and wait at least 10 seconds.
2. Turn ignition switch ON.
3. Turn ignition switch OFF and wait at least 10 seconds.

TESTING CONDITION: Before performing the following procedure, confirm that battery voltage is more than 10.5 V at idle.

>> GO TO 2.

2.CHECK A/F SENSOR FUNCTION

1. Start engine and warm it up to normal operating temperature.
2. Select "ENGINE" using CONSULT.
3. Select "A/F SEN1 (B1)" in "DATA MONITOR" mode.
4. Check "A/F SEN1 (B1)" indication.

Is the indication constantly approx. 0 V?

YES >> Go to EC, "Diagnosis Procedure".

NO >> GO TO 3.

3.PERFORM DTC CONFIRMATION PROCEDURE

1. Turn ignition switch OFF and wait at least 10 seconds and then restart engine.
2. Drive and accelerate vehicle to more than 40 km/h (25 MPH) within 20 seconds after restarting engine.

   CAUTION: Always drive vehicle at a safe speed.

3. Maintain the following conditions for about 20 consecutive seconds.

NOTE:

• Keep the accelerator pedal as steady as possible during cruising.
• If this procedure is not completed within 1 minute after restarting engine at step 1, return to step1.

    4.   Check 1st trip DTC.

Is 1st trip DTC detected?

YES >> Go to EC, "Diagnosis Procedure".

NO >> INSPECTION END

DTC Logic

Diagnosis Procedure