Schematic Reference: Theft Deterrent System Schematics

DEFINITION: The horn does not sound when the content theft deterrent (CTD) system is in alarm mode.

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

1. Install a scan tool.
2. Turn ON the ignition with the engine OFF.
3. With the scan tool, command the horn relay ON.

Does the horn sound?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Step 3

Press the horn switch on the steering wheel.

Does the horn sound?

Go to Step 4

Go to Horns Malfunction

1. Disconnect the body control module (BCM) connector containing the horn relay control circuit.
2. With a fused jumper wire and appropriate terminal adapter, ground the horn relay control circuit.

Does the horn sound?

Go to Step 6

Go to Step 5

Test the horn relay control circuit for an open or short to battery. Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 8

Go to Testing for Intermittent Conditions and Poor Connections

Inspect for poor connections at the harness connector of the BCM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 8

Go to Step 7

Replace the BCM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 8

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Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3