THEFT DETERRENT SYSTEM (w/ Smart Entry and Start System) Security Horn Circuit

DESCRIPTION

When the theft deterrent system is switched from the armed state to the alarm sounding state, the certification ECU (smart key ECU assembly) controls the security horn.

WIRING DIAGRAM

A017DQAE03

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK HARNESS AND CONNECTOR (CERTIFICATION ECU - ENGINE ROOM JUNCTION BLOCK)


    1. A017B6TE03

      Disconnect the D35 ECU connector.

    2. Connect a negative battery lead to terminal 20 (SH-) of the D35 ECU connector.

    3. Check operation of the security horn.

      OK
      Measurement Condition Specified Condition
      Battery negative (-) → D35-20 (SH-) Horn sounds

    NG

    INSPECT SECURITY HORN ASSEMBLY Click here

    OK

    PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE Click here

  2. INSPECT SECURITY HORN ASSEMBLY


    1. A017C70

      Remove the security horn assembly.

    2. Connect a positive battery lead to terminal 1 of the security horn assembly, and a negative battery lead to the horn body.

    3. Check operation of the horn.

      OK
      Measurement Condition Specified Condition
      Battery positive (+) → Terminal 1 Horn sounds
      Battery negative (-) → Horn body

    NG

    REPLACE SECURITY HORN ASSEMBLY Click here

    OK

  3. CHECK HARNESS AND CONNECTOR (ENGINE ROOM JUNCTION BLOCK - SECURITY HORN ASSEMBLY)


    1. A017G55E02

      Disconnect the 2A engine room junction block connector and A16 security horn assembly connector.

    2. Measure the resistance according to the value(s) in the table below.

      Standard resistance
      Tester Connection Condition Specified Condition
      2A-5 - A16-1 Always Below 1 Ω
      2A-5 - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. CHECK HARNESS AND CONNECTOR (BATTERY - ENGINE ROOM JUNCTION BLOCK)


    1. A017F0RE02

      Disconnect the 2G engine room junction block connector.

    2. Measure the voltage on the junction block side according to the value(s) in the table below.

      Standard voltage
      Tester Connection Condition Specified Condition
      2G-1 - Body ground Always 11 to 14 V

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  5. CHECK HARNESS AND CONNECTOR (ENGINE ROOM JUNCTION BLOCK - CERTIFICATION ECU)


    1. Disconnect the 2D engine room junction block connector.

    2. Disconnect the D35 ECU connector.

    3. Measure the resistance according to the value(s) in the table below.

      A017CCIE01
      Standard resistance
      Tester Connection Condition Specified Condition
      2D-11 - D35-20 (SH-) Always Below 1 Ω
      D35-20 (SH-) - Body ground Always 10 kΩ or higher

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ENGINE ROOM JUNCTION BLOCK