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A Symptoms - Horns

SYMPTOMS

IMPORTANT: The following steps must be completed before using the symptom tables.

1. Perform Diagnostic System Check - Horns before using the symptom tables in order to verify that all of the following are true:
- There are no DTCs set.
- The body control module (BCM) can communicate via the serial data link. Diagnostic System Check - Horns
2. Review the system operation in order to familiarize yourself with the system functions. Refer to Horns System Description and Operation

Visual/Physical Inspection
Several of the symptom procedures ask for a careful visual/physical inspection. This step is extremely important, it could lead to correcting a problem without further checks and can save valuable time. These checks include the following:
- Inspect for aftermarket devices which could affect the operation of the Horn System.
- Inspect the easily accessible or visible system components and harness connectors for obvious damage or conditions which could cause the symptom.

NOTE: Refer to Fastener Notice in Service Precautions.

Perform the following if the horns buzz or have a harsh tone:
- Inspect for debris in the joints where the horns fasten to the vehicle.
- Test the torque of the horn mounting hardware. The horn mounting hardware should be tightened to a torque of 10 N.m (7 lb ft).

Intermittents
Faulty electrical connections or wiring may be the cause of intermittent conditions.

Symptom List
Refer to a symptom diagnostic procedure from the following list in order to diagnose a symptom that does not set a DTC:
- Horns Always On
- Horns Inoperative
- Horns Inoperative - One Horn
- Horns - Poor Tone