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Nissan Sentra B18 (2020-2025) Service Manual: C1621-86 Bcm System

Dtc Description

DTC Description

DTC DETECTION LOGIC

DTC No.

CONSULT screen terms

(Trouble diagnosis content)

DTC detection condition

C1621-86

BCM system

(Body control module system)

Diagnosis condition

When ignition switch is ON.

Signal (terminal)

CAN communication signal

Threshold

When a malfunction is detected in BCM.

Diagnosis delay time

2 seconds or more

POSSIBLE CAUSE

  • CAN communication line

  • BCM

  • EPS control unit

FAIL-SAFE

Normal control

Confirmation Procedure

Confirmation Procedure

  1. PRECONDITIONING

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

    >>

    GO TO 2.

  2. DTC REPRODUCTION PROCEDURE

    1. CONSULT

      1. Ignition switch ON.

      2. Select "Self Diagnostic Result" mode of “EPS/DAST 3”.

    Is DTC “C1621-86” detected?

    YES >>

    Proceed to diagnosis procedure. Refer to DTC Diagnosis Procedure.

    NO >>

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

    NO >>

    Confirmation after repair: Inspection End.

Dtc Diagnosis Procedure

DTC Diagnosis Procedure

  1. PERFORM SELF DIAGNOSTIC RESULT

    1. CONSULT

      1. Ignition switch ON.

      2. Select "Self Diagnostic Result" mode of “BCM”.

    Is any DTC detected?

    YES>>

    Check the DTC. Refer to DTC Index.

    NO>>

    GO TO 2.

  2. CHECK CONNECTOR AND TERMINAL

      1. Ignition switch OFF.

      2. Disconnect BCM harness connector.

      3. Disconnect EPS control unit harness connector.

      4. Check the connector for disconnection or looseness.

      5. Check the pin terminals for damage or loose connection with harness connector.

    Is the inspection result normal?

    YES>>

    GO TO 3.

    NO>>

    Repair or replace harness, connector, or terminal, securely lock the connector.

  3. PERFORM SELF DIAGNOSTIC RESULT

    1. CONSULT

      1. Connect BCM harness connector.

      2. Connect EPS control unit harness connector.

      3. Ignition switch ON.

      4. Erase "Self Diagnostic Result" mode of "EPS/DAST 3".

      5. Ignition switch OFF and wait for at least 10 seconds.

      6. Ignition switch ON.

      7. Select "Self Diagnostic Result" mode of “EPS/DAST 3”.

    Is DTC “C1621-86” detected?

    YES>>

    EPS control unit is malfunctioning. Replace steering gear assembly. Refer to Removal and Installation.

    NO>>

    Inspection End.

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