For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Driver Door Key Switch Signal | 1 | 1 | 1 | --
Driver Door Key Switch Ground | -- | 1 | 1 | --
1. Content theft deterrent will not disarm using door key

### Circuit/System Description

The content theft deterrent system is a software based system in which the body control module actively monitors certain inputs to determine if unauthorized vehicle access is being attempted. The driver door lock cylinder switch is used as an input to disarm the content theft deterrent system. The driver door module monitors the driver door key switch signal circuit to determine if the driver door cylinder is being rotated, indicating a vehicle key is being used to unlock the vehicle and the content theft deterrent system should be disarmed. The door key cylinder switch, located in the door latch assembly, provides a switched ground for the signal circuit body control module.

### Reference Information

#### Schematic Reference

Door Lock/Indicator Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Content Theft Deterrent (CTD) Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

Ignition ON, verify the scan tool Driver Door Key Cylinder Lock/Unlock Switch parameter cycles between Inactive and Active while turning the driver door lock cylinder with the vehicle key.

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the A23D driver door latch assembly.
2. Ignition OFF, test for less than 10 Ω between the ground circuit terminal 8 and ground.

⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the A15 body control module.

3. Ignition ON, verify the scan tool Driver Door Key Cylinder Lock/Unlock Switch parameter is Inactive.

⇒ | If not the specified value, test the signal circuit terminal for a short to ground. If the circuit tests normal, replace the A15 body control module.

4. Install a 3 A fused jumper wire between the signal circuit terminal and ground. Verify the scan tool Driver Door Key Cylinder Lock/Unlock Switch parameter is Active.

⇒ | If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K9 body control module.

5. If all circuits test normal, test or replace the A23D driver door latch assembly.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Front Side Door Lock Replacement

• | Control Module References for driver door module replacement, setup, and programming.