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 CTD system will not ARM or DISARM properly.

1

Did you perform the Theft Deterrent Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Theft Deterrent

2

Important: When the CTD system is armed, the vehicle will confirm by chirping the alarm and flashing the turn signals once.

  1. Open the driver and passenger windows.
  2. Remove the keys from the ignition.
  3. Close all the doors, rear compartment and the hood.
  4. Lock the doors with the transmitter. (Arm the system.)

Did the CTD system arm?

Go to Step 3

Go to Step 4

3

Important: When the CTD system is disarmed, the vehicle will confirm by flashing the turn signals twice.

With the system still armed, unlock a door with the key.

Does the CTD system disarm?

Go to Testing for Intermittent Conditions and Poor Connections

Go to Content Theft Deterrent (CTD) Does Not Disarm with Key Lock

4

Test for a poor connection at the theft deterrent alarm. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 5

Go to Symptoms - Lighting Systems

5

  1. Switch the dome lamp to the center position (DOOR).
  2. Unlock the doors with the transmitter.
  3. Observe the courtesy lamps.
  4. Open and close each door.

Do the courtesy lamps illuminate for all doors?

Go to Step 9

Go to Step 6

6

  1. Disconnect the hood switch.
  2. Attempt to arm the CTD system.

Does the CTD system arm?

Go to Step 11

Go to Step 7

7

Test for a short to ground in the hood switch signal circuit. Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 8

8

Test for a poor connection at the ISU. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 12

9

Test for a short to ground in the key reminder circuit. Refer to Testing for Short to Ground and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 13

Go to Step 10

10

Replace the ignition switch. Refer to Ignition Lock Cylinder Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 13

--

11

Replace the hood switch. Refer to Hood Ajar Indicator Lamp Switch Replacement .

Did you complete the replacement?

Go to Step 13

--

12

Important:  Perform the program procedure for the ISU.

Replace the ISU. Refer to Intelligent Switching Unit Replacement in Body Control Systems.

Did you complete the replacement?

Go to Step 13

--

13

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2