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Diagnosis Procedure

  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 horn function using horn switch.

    Do the horn sound? 

    YES: GO TO 3.

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

  3. CHECK HORN CONTROL CIRCUIT 1 
    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
      E6 44 E11 1 Existed
    4. Check continuity between IPDM E/R harness connector and ground.
      IPDM E/R Ground Continuity
      Connector Terminal
      E6 44 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
      E18 1 Ground Battery voltage

      Is the inspection result normal? 

      YES: GO TO 5.

      NO: Repair or replace harness.

  5. CHECK HORN CONTROL CIRCUIT 2 
    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 Theft warning horn relay Continuity
      Connector Terminal Connector Terminal
      E6 45 E18 3 Existed
    3. Check continuity between IPDM E/R harness connector and ground.
      IPDM E/R Ground Continuity
      Connector Terminal
      E6 45 Not existed

      Is the inspection result normal? 

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

      NO: Repair or replace harness.