2004 Nissan-Datsun Sentra SE-RFACTORY OEM SERVICE PROCEDURE

Check Security Horn Operation

WARNING: This page is about a different car, the 2003 Infiniti M45. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK SECURITY HORN CHIRP OPERATION 

    With CONSULT-II 

    1. Check security horn chirp "HORN" in "ACTIVE TEST" mode with CONSULT-II.
    2. Perform operation shown on display.
      1. Security horn should sound. 
      Fig 1: Display Active Test Sheet With Consult-II
      G02022413Courtesy of NISSAN MOTOR CO., U.S.A.

    Without CONSULT-II 

    1. Disconnect BCM connector.
      Fig 2: Disconnecting BCM Connector
      G02022414Courtesy of NISSAN MOTOR CO., U.S.A.
    2. Apply ground to BCM connector E204 terminal 127 (P/L).
      1. Security horn should sound. 

    OK or NG 

    OK >> Security horn alarm is OK.

    NG >> GO TO 2.

  2. CHECK SECURITY HORN RELAY 

    Check security horn relay condition.

    OK or NG 

    OK >> GO TO 3.

    NG >> Replace security horn relay.

  3. CHECK POWER SUPPLY FOR SECURITY HORN RELAY 
    1. Disconnect security horn relay connector.
    2. Check voltage between security horn relay connector E77 terminal 2 (Y/B) and ground.
      1. 2 (Y/B) - Ground : Battery voltage 
      3. Fig 3: Checking Voltage Between Security Horn Relay Connector And Ground
      G02022415Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK >> GO TO 4.

    NG >> Check the following.

    • 10A fuse [No. 78, located in the fuse, fusible link and relay block (J/B)]
    • Harness for open or short between security horn relay and fuse
  4. CHECK SECURITY HORN RELAY CIRCUIT 
    1. Disconnect BCM and security horn relay connector.
    2. Check continuity between BCM connector E204 terminal 127 (P/L) and security horn relay connector E77 terminal 1 (P/L).
      1. 127 (P/L) - 1 (P/L) : Continuity should exist. 

    OK or NG 

    OK >> GO TO 5.

    NG >> Repair or replace harness.

    Fig 4: Checking Security Horn Relay Circuit
    G02022416Courtesy of NISSAN MOTOR CO., U.S.A.
  5. CHECK SECURITY HORN RELAY CIRCUIT 
    1. Disconnect security horn relay and security horn connector.
    2. Check continuity between security horn relay connector E77 terminal 3 (P/B) and security horn connector E30 terminal 1 (P/B).
      1. 3 (P/B) - 1 (P/B) : Continuity should exist. 
      3. Fig 5: Checking Continuity Between Security Horn Relay Connector & Security Horn Connector
      G02022417Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK >> Replace security horn.

    NG >> Repair or replace harness.

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