LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Infiniti >> 2012 >> G25 Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 82 (Security Control System) >> DTC/Circuit Diagnosis >> Horn Function >> Diagnosis Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnosis Procedure

WARNING: This page is about a different car, the 2011 Nissan 370Z. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK HORN SWITCH

    Check horn function with horn switch

    Do the horns sound? 

    YES: Go to 2.

    NO: Refer to "WIRING DIAGRAM - HORN - ".

  2. CHECK HORN RELAY POWER SUPPLY
    1. Turn ignition switch ON.
    2. Perform "ACTIVE TEST" ("HORN") using CONSULT-Ill.
    3. Check voltage between malfunctioning horn relay harness connector and ground.
      TEST ITEM DESCRIPTION

      (+) (-) Test item Voltage (V) (Approx.)
      Horn relay
      Connector Terminal
      Low E11 1 Ground HORN ON Battery voltage → 0 → Battery voltage
      High E18 3 Other than above Battery voltage

      Is the inspection result normal? 

      YES: Go to  4.

      NO: Go to 3.

  3. CHECK HORN RELAY CIRCUIT
    1. Turn ignition switch OFF.
    2. Disconnect IPDM E/R connector and horn relay.
    3. Check continuity between IPDM E/R harness connector and malfunctioning horn relay terminal connector.
      CONTINUITY SPECIFICATION

      IPDM E/R Horn relay Continuity
      Connector Terminal Connector Terminal
      E6 44 E11 1 Existed
      45 E18 3
    4. Check continuity between IPDM E/R harness connector and ground.
      CONTINUITY SPECIFICATION

      IPDM E/R Ground Continuity
      Connector Terminal
      E6 44 Not existed
      45

      Is the inspection result normal? 

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

      NO: Repair or replace harness.

  4. CHECK INTERMITTENT INCIDENT

    Refer to "INTERMITTENT INCIDENT ".

    Is the inspection result normal? 

    INSPECTION END