Factory-style information for owners and repair work

Nissan Sentra techinfo

Find Nissan Sentra owner information, maintenance instructions, technical references, service procedures and useful repair pages in one clean online library.

Nissan Sentra B18 (2020-2025) Service Manual: P0401 Egr Function

Dtc Description

DTC Description

DTC DETECTION LOGIC

DTC

CONSULT screen terms

(Trouble diagnosis content)

DTC detection condition

P0401

EGR A FLOW INSUFFICIENT

(EGR "A" flow insufficient detected)

Diagnosis condition

—

Signal (terminal)

EGR volume control valve

Threshold

When ECM detects that negative pressure variation in intake manifold is smaller than the variation corresponding to EGR valve opening in case of opening/closing EGR control valve in a condition fuel supply is cut.

Diagnosis delay time

—

POSSIBLE CAUSE

  • EGR cooler clogged

  • EGR pipe clogged

  • Incorrect EGR pipe connection

FAIL-SAFE

Engine Control System

Engine operating condition in fail-safe mode

Fail safe mode

Nissan Sentra Vehicle behavior

Device fix mode

  • This mode fixes the electric IVT motor and the EVT control solenoid valve in the reference position.

  • The intake manifold runner control valve motor is turned OFF (intake manifold runner control valve opens).

Idle Start/Stop System

Not applicable

Confirmation Procedure

Confirmation Procedure

  1. PRECONDITIONING

    If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at least 10 seconds before conducting the next test.

    TESTING CONDITION:

    Before performing the following procedure, confirm that battery voltage is more than 11 V at idle.

    >>

    GO TO 2.

  2. PERFORM DTC CONFIRMATION PROCEDURE

    1. Start engine and warm it up to normal operating temperature.

    2. Drive the Nissan Sentra vehicle at 80 km/h (50 MPH).

      CAUTION:

      Always drive vehicle at a safe speed.

    3. Release the accelerator pedal fully until the Nissan Sentra vehicle speed decreases to 40 km/h (25 MPH).

    4. Check 1st trip DTC.

    Is 1st trip DTC detected?

    YES >>

    Refer to DTC Diagnosis Procedure.

    NO-1 >>

    To check malfunction symptom before repair: Refer to Intermittent Incident.

    NO-2 >>

    Confirmation after repair: INSPECTION END

Dtc Diagnosis Procedure

DTC Diagnosis Procedure

  1. CHECK EGR PASSAGE

    Check the following parts for clogging and damage.

    • EGR tube

    • EGR hose

    • EGR cooler

    Is the inspection result normal?

    YES >>

    GO TO 2.

    NO >>

    Repair or replace malfunctioning part

  2. CHECK EGR VOLUME CONTROL VALVE VISUALLY

    1. Remove EGR volume control. Refer to Removal and Installation.

    2. Check if foreign matter is caught between the EGR volume control valve and the housing.

    Is the inspection result normal?

    YES >>

    GO TO 3.

    NO >>

    Repair or replace malfunctioning part.

  3. CHECK EGR COOLER VISUALLY

    1. Remove EGR cooler. Refer to Removal and Installation.

    2. Check if foreign matter is caught between the EGR cooler and the housing.

    Is the inspection result normal?

    YES >>

    INSPECTION END

    NO >>

    Repair or replace malfunctioning part.

    P0365 Exhaust Valve Timing Control Position Sensor
    Dtc Description DTC Description DTC DETECTION LOGIC DTC CONSULT screen terms (Trouble diagnosis content) DTC detection condition P0365 CMP SEN/CIRC-B1 (Camshaft position sensor ...
    P0402 Egr System
    Dtc Description DTC Description DTC DETECTION LOGIC DTC CONSULT screen terms (Trouble diagnosis content) DTC detection condition P0402 EGRC-BPT VALVE (EGR A flow excessive detec...

    Other materials:

    Front Disc Brake
    Inspection - Front Brake Pad Inspection - Front Brake Pad INSPECTION Check brake pad wear thickness from an inspection hole (A) on cylinder body. Wear thickness : Refer to Front Disc Brake. ...

    U2118-87 Can Comm Circuit
    Dtc Description DTC Description CAN (Controller Area Network) is a serial communication system for real time application. It is an on-Nissan Sentra vehicle multiplex communication system with high data communication speed and excellent error detectability. Many electronic control un ...

    Specifications
    Engine This spark ignition system complies with the Canadian standard ICES-002. Wheels and tires Dimensions and weights When traveling or registering in another country If you plan to operate your Nissan Sentra in another country, first verify that the available fuel meets the ...