GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Theft Deterrent System Schematics

Connector End View Reference: Theft Deterrent System Connector End Views

DEFINITION: The horn does not sound when the Content Theft Deterrent (CTD) System is in alarm mode.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

Perform the following to activate the CTD alarm mode:

  1. Open the driver window.
  2. Lock the vehicle using the power door locks or the keyless entry transmitter.
  3. Close all the doors.
  4. Wait for the theft LED to transition from on solid to flashing slowly.
  5. Reach in and manually unlock the driver door.
  6. Open the driver door.

Do all of the alarm mode functions activate, lights flash and horn pulses?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

Are only the horns inoperative?

Go to Horns Inoperative in Horns

Go to Content Theft Deterrent (CTD) Alarm Mode Inoperative