Diagnostic Routine B

Diagnostic Routine B

Diagnostic Overview

The Courtesy Lamps Do Not Illuminate With The Liftgate Open

Refer to Wiring Diagram Set 109 for schematic and connector information Electrical Diagrams.

Refer to Wiring Diagram Set 117 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

REFER to Courtesy Lamps .

Visual Inspection and Diagnostic Pre-checks

- Inspect the door for correct latching.

DTC Fault Trigger Conditions






Visual Inspection and Diagnostic Pre-checks

- Inspect the liftgate for correct latching.

Pinpoint Test

1. CHECK THE COURTESY LAMP OPERATION FROM ANY DOOR
NOTE: Make sure that the dark car feature is not enabled in the BCM (Body Control Module). The dark car feature disables activation of courtesy lamps due to a door unlock, door ajar or removing the key from the ignition cylinder. The feature can be disabled using a scan tool.

1. Ignition OFF.

2. Open any door and observe the courtesy lamps.

Do the courtesy lamps illuminate?








2. CHECK THE LTM (Liftgate/Trunk Module) OR THE LIFTGATE LATCH

1. Disconnect: Liftgate Latch C4174B.

Do the courtesy lamps illuminate?








3. CHECK THE LIFTGATE AJAR INPUT CIRCUIT FOR A SHORT TO GROUND

1. Disconnect: BCM (Body Control Module) C2280C.

2. Measure:





Is the resistance greater than 10,000 ohms?








4. CHECK FOR CORRECT LTM (Liftgate/Trunk Module) OPERATION

1. Disconnect the LTM (Liftgate/Trunk Module) connectors.

2. Repair:

- corrosion (install new connector or terminals - clean module pins)
- corrosion (install new connector or terminals - clean module pins)
- pushed-out pins - install new pins as necessary

3. Reconnect the LTM (Liftgate/Trunk Module) connectors and make sure they seat and latch correctly.

4. Operate the system and determine if the concern is still present.

Is the concern still present?








5. CHECK FOR CORRECT BCM (Body Control Module) OPERATION

1. Disconnect the BCM (Body Control Module) connectors.

2. Repair:

- corrosion (install new connector or terminals - clean module pins)
- corrosion (install new connector or terminals - clean module pins)
- pushed-out pins - install new pins as necessary

3. Reconnect the BCM (Body Control Module) connectors and make sure they seat and latch correctly.

4. Operate the system and determine if the concern is still present.

Is the concern still present?