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Diagnosis Procedure

WARNING: This page is about a different car, the 2012 Infiniti QX56. However, it is still accessible from the selected car via links, so may be relevant.
  1. INSPECTION START

    Perform inspection in accordance with procedure that confirms malfunction.

    Which procedure confirms malfunction? 

    Component Function Check 1: GO TO 2.

    Component Function Check 2: GO TO  4.

  2. CHECK HORN FUNCTION

    Check that horns function properly using horn switch.

    Do horns sound? 

    YES: GO TO 3.

    NO: Check horn circuit. Refer to "WIRING DIAGRAM ".

  3. CHECK HORN CONTROL CIRCUIT
    1. Disconnect horn relay.
    2. Disconnect IPDM E/R connector.
    3. Check continuity between IPDM E/R harness connector and horn relay harness connector.
      IPDM E/R Horn relay Continuity
      Connector Terminal Connector Terminal
      E13 34 E5 1 Existed
    4. Check continuity between IPDM E/R harness connector and ground.
      IPDM E/R Ground Continuity
      Connector Terminal
      E13 34 Not existed

      Is the inspection result normal? 

      YES: Replace IPDM E/R. Refer to "REMOVAL AND INSTALLATION ".

      NO: Repair or replace harness.

  4. CHECK VEHICLE SECURITY HORN RELAY POWER SUPPLY
    1. Disconnect vehicle security horn relay.
    2. Check voltage between vehicle security horn relay harness connector and ground.
      (+) (-) Voltage (V) (Approx.)
      Vehicle security horn relay
      Connector Terminal
      E124 1 Ground Battery voltage

      Is the inspection result normal? 

      YES: GO TO 5.

      NO-1: Check 10 A fuse [No. 36 located in the fuse block (J/B)].

      NO-2: Check harness for open or short between vehicle security horn relay and fuse.

  5. CHECK VEHICLE SECURITY HORN CONTROL CIRCUIT
    1. Disconnect IPDM E/R connector.
    2. Check continuity between IPDM E/R harness connector and vehicle security horn relay harness connector.
      IPDM E/R Vehicle security horn relay Continuity
      Connector Terminal Connector Terminal
      E13 34 E124 3 Existed
    3. Check continuity between IPDM E/R harness connector and ground.
      IPDM E/R Ground Continuity
      Connector Terminal
      E13 34 Not existed

      Is the inspection result normal? 

      YES: GO TO 6.

      NO: Repair or replace harness.

  6. CHECK VEHICLE SECURITY HORN CIRCUIT
    1. Disconnect vehicle security horn connector.
    2. Check continuity between vehicle security horn relay harness connector and vehicle security horn harness connector.
      Vehicle security horn relay Vehicle security horn Continuity
      Connector Terminal Connector Terminal
      E124 2 E125 1 Existed
    3. Check continuity between vehicle security horn relay harness connector and ground.
      Vehicle security horn relay Ground Continuity
      Connector Terminal
      E124 2 Not existed

      Is the inspection result normal? 

      YES: GO TO 7.

      NO: Repair or replace harness.

  7. CHECK VEHICLE SECURITY HORN RELAY

    Refer to "COMPONENT INSPECTION ".

    Is the inspection result normal? 

    YES: Replace vehicle security horn.

    NO: Replace vehicle security horn relay.

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