For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
Schematic Reference: Theft Deterrent System Schematics Connector End View Reference: Component 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 | --
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