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
NOTICE:
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PROCEDURE
1. | PERFORM ACTIVE TEST USING TECHSTREAM (SECURITY HORN) |
(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 Horn | Security horn Assembly | OFF/ON | - |
Tester Display |
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Security Horn |
OK:
The security horn assembly sounds and stops correctly when operated through the Techstream.
OK | ![]() | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
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2. | INSPECT SECURITY HORN ASSEMBLY |
(a) Remove the security horn assembly.
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(b) Inspect the security horn assembly.
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NG | ![]() | REPLACE SECURITY HORN ASSEMBLY |
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3. | INSPECT S-HORN RELAY |
(a) Remove the S-HORN relay from the engine room relay block. |
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(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
3 - 5 | Battery voltage not applied between terminals 1 and 2 | 10 kΩ or higher |
3 - 5 | Battery voltage applied between terminals 1 and 2 | Below 1 Ω |
NG | ![]() | REPLACE S-HORN RELAY |
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4. | INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
(a) Remove the main body ECU (multiplex network body ECU).
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*a | Component without harness connected (Instrument Panel Junction Block Assembly) | - | - |
(b) Disconnect the 2C instrument panel junction block assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
2C-26 - MB-29 (SH) | Always | Below 1 Ω |
NG | ![]() | REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY |
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5. | CHECK HARNESS AND CONNECTOR (BATTERY - S-HORN RELAY) |
(a) Measure the voltage according to the value(s) in the table below. Standard Voltage:
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NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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6. | CHECK HARNESS AND CONNECTOR (S-HORN RELAY - SECURITY HORN ASSEMBLY) |
(a) Measure the resistance according to the value(s) in the table below. Standard Resistance:
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NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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7. | CHECK HARNESS AND CONNECTOR (S-HORN RELAY - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY) |
(a) Measure the resistance according to the value(s) in the table below. Standard Resistance:
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OK | ![]() | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
NG | ![]() | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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