DESCRIPTION
The theft warning siren assembly sounds if either of the following conditions is met:
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
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PROCEDURE
1. | PERFORM ACTIVE TEST USING TECHSTREAM (SECURITY HORN2) |
(a) Connect the Techstream to the DLC3.
(b) Turn the engine switch on (IG).
(c) Turn the Techstream on.
(d) Enter the following menus: Body Electrical / Main Body / Active Test.
(e) Perform the Active Test according to the display on the Techstream.
Body Electrical > Main Body > Active Test Tester Display | Measurement Item | Control Range | Diagnostic Note |
---|---|---|---|
Security Horn2 | Theft warning siren assembly | OFF/ON | - |
Tester Display |
---|
Security Horn2 |
OK:
The theft warning siren assembly sounds and stops correctly when operated using the Techstream.
OK | ![]() | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
|
2. | CHECK HARNESS AND CONNECTOR (BATTERY - THEFT WARNING SIREN ASSEMBLY - BODY GROUND) |
(a) Disconnect the R28 theft warning siren assembly connector. |
|
(b) Measure the voltage and resistance according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
---|---|---|
R28-1 (+B) - Body ground | Always | 11 to 14 V |
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
R28-3 (GND) - Body ground | Always | Below 1 Ω |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
3. | CHECK HARNESS AND CONNECTOR (MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) - THEFT WARNING SIREN ASSEMBLY) |
(a) Disconnect the J9 main body ECU (multiplex network body ECU) connector.
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
J9-18 (SSCL) - R28-2 (CONT) | Always | Below 1 Ω |
J9-18 (SSCL) or R28-2 (CONT) - Body ground | Always | 10 kΩ or higher |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
4. | REPLACE THEFT WARNING SIREN ASSEMBLY |
(a) Temporarily replace the theft warning siren assembly with a new or known good one.
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|
5. | CHECK THEFT WARNING SIREN ASSEMBLY |
(a) Turn the engine switch on (IG), then off.
(b) Set the theft deterrent system to "ARMED STATE".
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(c) Check that the security indicator changes from illuminated to blinking.
(d) Change the theft deterrent system to "ALARM SOUNDING STATE".
Click here
(e) Check that the theft warning siren assembly is sounding.
OK:
Theft warning siren assembly is sounding.
OK | ![]() | END (THEFT WARNING SIREN ASSEMBLY WAS DEFECTIVE) |
NG | ![]() | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
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