THEFT DETERRENT SYSTEM (w/o Intrusion Sensor) Theft Warning Siren Circuit

DESCRIPTION

• The theft warning siren has an internal battery. If the vehicle auxiliary battery or any of the communication lines are open, the theft warning siren detects this and sounds its siren.

• Although the theft warning siren usually sounds by receiving a signal from the main body ECU (multiplex network body ECU), the theft warning siren can sound by its internal battery in case the vehicle auxiliary battery is open.

• The main body ECU (multiplex network body ECU) sends an arming signal to the theft warning siren while transferring to the armed state, and it also sends a disarming signal to the siren while switching to the disarmed state. Also, the main body ECU (multiplex network body ECU) can cause the theft warning siren to sound by sending an alarm signal during the alarm sounding state.

WIRING DIAGRAM

INSPECTION PROCEDURE

PROCEDURE

1. PERFORM ACTIVE TEST USING INTELLIGENT TESTER (THEFT WARNING SIREN)

   
   

   1. Connect the intelligent tester to the DLC3.

   2. Turn the power switch on (IG).

   3. Turn the intelligent tester on.

   4. Select the item below in the Active Test and then check that the theft warning siren operates.

   5. Operate the intelligent tester according to the steps on the display and select "Active Test".

      Main Body

      Tester Display	Test Part	Control Range	Diagnostic Note
      Security Horn2	Theft warning siren	ON / OFF	-

      OK
      The theft warning siren sounds and stops correctly when operated though the intelligent tester.

   
   

   NG

   CHECK THEFT WARNING SIREN Click here

   OK

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

2. CHECK THEFT WARNING SIREN

   
   

   1. 

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

      Standard Voltage

      Tester Connection Condition Specified Condition O38-1 (+B) - Body ground Power switch off 11 to 14 V O38-2 (GND) - Body ground Always Below 1 V O38-3 (CONT) - Body ground When switched from armed state or arming preparation state to disarmed state (1) Wave pattern (1) shown in chart below When switched from arming preparation state to armed state (2) Wave pattern (2) shown in chart below Normal condition (Except (1) and (2)) Approx. 1.4 V

   2. Wave pattern

      

   
   

   NG

   CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - THEFT WARNING SIREN) Click here

   OK

   REPLACE THEFT WARNING SIREN Click here

3. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU - THEFT WARNING SIREN)

   

   Text in Illustration

   *1	Front view of wire harness connector (to Main Body ECU (Multiplex Network Body ECU))
   *2	Front view of wire harness connector (to Theft Warning Siren)

   
   

   1. Disconnect the F14 main body ECU (multiplex network body ECU) and O38 theft warning siren connectors.

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

      Standard Resistance
      Tester Connection Condition Specified Condition F14-18 (SSCL) - O38-3 (CONT) Always Below 1 Ω F14-18 (SSCL) - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

4. CHECK HARNESS AND CONNECTOR (THEFT WARNING SIREN - BODY GROUND)

   

   Text in Illustration

   *1	Front view of wire harness connector (to Theft Warning Siren)

   
   

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

      Standard Resistance
      Tester Connection Condition Specified Condition O38-2 (GND) - Body ground Always Below 1 Ω

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

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