THEFT DETERRENT SYSTEM Security Horn Circuit

DESCRIPTION

When the theft deterrent system is switched from the armed state to the alarm sounding state, the main body ECU (multiplex network body ECU) transmits a signal to cause the security horn assembly to sound at intervals of 0.4 seconds.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. PERFORM ACTIVE TEST USING GTS (SECURITY HORN)

   
   

   1. Connect the GTS to the DLC3.

   2. Turn the ignition switch to ON.

   3. Turn the GTS on.

   4. Enter the following menus: Body Electrical / Main Body / Active Test.

   5. Perform the Active Test according to the display on the GTS.

      
      Body Electrical > Main Body > Active Test

      Tester Display	Measurement Item	Control Range	Diagnostic Note
      Security Horn	Security horn Assembly	OFF/ON	-

      
      Body Electrical > Main Body > Active Test

      Tester Display
      Security Horn

      OK
      The security horn assembly sounds and stops correctly when operated through the GTS.

      Result
      Result Proceed to OK (for LHD) A OK (for RHD) B NG C

   
   

   A

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   B

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   C

2. INSPECT SECURITY HORN ASSEMBLY

   
   

   1. Remove the security horn assembly.

      Click here

   2. Inspect the security horn assembly.

      Click here

      Result
      Proceed to OK NG

   
   

   NG

   REPLACE SECURITY HORN ASSEMBLY Click here

   OK

3. INSPECT S-HORN RELAY

   
   

   1. Remove the S-HORN relay from the No. 4 relay block assembly.

   2. Inspect the S-HORN relay.

      Click here

      Result
      Proceed to OK NG

   
   

   NG

   REPLACE S-HORN RELAY

   OK

4. INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

   
   

   1. Remove the main body ECU (multiplex network body ECU).

      
      

      • for LHD: Click here

      • for RHD: Click here

      

      *a

      Component without harness connected (Instrument Panel Junction Block Assembly)

      -

      -

   2. Disconnect the 3A instrument panel junction block assembly connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition 3A-20 - MB-29 (SH) Always Below 1 Ω

      Result
      Result Proceed to OK A NG (for LHD) B NG (for RHD) C

   
   

   B

   REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

   C

   REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here

   A

5. CHECK HARNESS AND CONNECTOR (BATTERY - S-HORN RELAY)

   
   

   1. Remove the S-HORN relay from the No. 4 relay block assembly.

   2. 

      *1	No. 4 Relay Block Assembly

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

      Standard Voltage
      Tester Connection Condition Specified Condition No. 4 relay block assembly S-HORN relay terminal 1 - Body ground Always 11 to 14 V No. 4 relay block assembly S-HORN relay terminal 5 - Body ground Always 11 to 14 V

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

6. CHECK HARNESS AND CONNECTOR (S-HORN RELAY - SECURITY HORN ASSEMBLY)

   
   

   1. Remove the S-HORN relay from the No. 4 relay block assembly.

   2. Disconnect the A15 security horn assembly connector.

   3. 

      *1	No. 4 Relay Block Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition No. 4 relay block assembly S-HORN relay terminal 3 - A15-1 Always Below 1 Ω No. 4 relay block assembly S-HORN relay terminal 3 or A15-1 - Body ground Always 10 kΩ or higher

      Result
      Proceed to OK NG

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

7. CHECK HARNESS AND CONNECTOR (S-HORN RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

   
   

   1. Remove the S-HORN relay from the No. 4 relay block assembly.

   2. Disconnect the 3A instrument panel junction block assembly connector.

   3. 

      *1	No. 4 Relay Block Assembly

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

      Standard Resistance
      Tester Connection Condition Specified Condition No. 4 relay block assembly S-HORN relay terminal 2 - 3A-20 Always Below 1 Ω No. 4 relay block assembly S-HORN relay terminal 2 or 3A-20 - Body ground Always 10 kΩ or higher

      Result
      Result Proceed to OK (for LHD) A OK (for RHD) B NG C

   
   

   A

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   B

   REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here

   C

   REPAIR OR REPLACE HARNESS OR CONNECTOR