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".
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(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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