THEFT DETERRENT SYSTEM > Security Horn Circuit |

| 1.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SECURITY HORN) |
Select the Active Test, use the intelligent tester to generate a control command, and then check that the security horn sounds.
| Item | Test Details | Diagnostic Note |
| Security Horn | Security horn ON/OFF | - |
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| OK | ||
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| 2.INSPECT SECURITY HORN ASSEMBLY |
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Remove the security horn.
Check operation of the horn.
| Measurement Condition | Specified Condition |
| Battery positive (+) → Terminal 1 Battery negative (-) → Horn bracket | Horn sounds |
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| OK | |
| 3.CHECK WIRE HARNESS (MULTIPLEX NETWORK BODY ECU - SECURITY HORN ASSEMBLY) |
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Disconnect the A41 ECU connector.
Disconnect the A28 horn connector.
Check the resistance of the wire harness side connectors.
| Tester Connection | Specified Condition |
| A41-1 (SH) - A28-1 | Below 1 Ω |
| A41-1 (SH) or A28-1 - Body sound | 10 kΩ or higher |
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| OK | ||
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