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 content theft deterrent (CTD) alarm does not disarm when using a key in any door or rear compartment lock cylinder.

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Turn ON the ignition, with the engine OFF.
  2. Install a scan tool.
  3. Select the ISU Central Door Locking Data Display.

Does the Tamper Switch parameter display INACTIVE?

Go to Step 3

Go to Step 6

3

Unlock the inoperative key lock.

Does the Tamper Switch parameter display ACTIVE?

Go to Step 8

Go to Step 4

4

  1. Disconnect the inoperative tamper switch connector.
  2. Test for an open in the tamper switch ground circuit. Refer to Testing for Continuity and Wiring Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 5

5

Test for an open in the door lock tamper switch signal circuit. Refer to Testing for Continuity and Wiring Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 7

6

Test for a short to ground in the door lock tamper switch circuits. Refer to Testing for Short to Ground and Wiring Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 7

7

Test for a poor connection at the inoperative door lock tamper switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 9

8

Test for a poor connection at the intelligent switching unit (ISU). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 10

9

Replace the inoperative lock tamper switch. Refer to Front Side Door Lock Replacement or Rear Compartment Lid Lock Cylinder Replacement .

Did you complete the replacement?

Go to Step 11

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10

Important:  Perform the program procedure for the ISU.

Replace the ISU.

Did you complete the replacement?

Go to Step 11

--

11

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2