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Horn Fails to Sound When Alarm Is Tripped

HORN FAILS TO SOUND WHEN ALARM IS TRIPPED

POSSIBLE CAUSES
- DTC present
- Horn circuit
- Instrument cluster

1. HORN RELAY CONTROL CIRCUIT DTC ACTIVE
Turn the ignition on.
With the DRBIII(R), read FCM DTC's.

Q: Does the DRBIII(R) display a HORN RELAY CONTROL CIRCUIT DTC active?

YES: Refer to the Ignition, Power, Accessory category for the related symptom(s). Perform VTSS VERIFICATION TEST - 1A. VTSS Verification Test
NO: Go To 2

2. HORN CIRCUIT DIAGNOSTICS

Q: Does the horn operate from the horn button?

YES: Replace and program the Instrument Cluster. Perform Body Verification Test - Ver 1. Body Verification Test
NO: Refer to symptom Horns Inoperative in the Ignition, Power, Accessory category. Perform VTSS VERIFICATION TEST - 1A. VTSS Verification Test