The body control module (BCM) applies battery voltage to the courtesy lamps through the courtesy lamp supply voltage circuit. When any door is opened, the jam switch contacts close and the BCM receives a door-open input. If the BCM receives a door lock or unlock input or a rear hatch open input, the BCM will activate the courtesy lamp supply voltage circuit, providing battery voltage to all of the instrument panel (I/P) courtesy lamps and rear compartment lamps. In the event that any of these lamps were to remain illuminated for more than 20 minutes with the ignition switch in the OFF position, the BCM will deactivate the inadvertent power courtesy lamp control circuit to prevent a total battery discharge condition.

Schematic Reference

Interior Lights Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Interior Lighting Systems Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

1. Ignition ON, command the Courtesy Lamps output control ON and OFF with the scan tool. The interior courtesy lamps should turn ON and OFF.

⇒	If one or more of the courtesy lamps are always ON or always OFF, refer to Courtesy Lamp Malfunction.

2. Ignition ON, all doors closed, observe the scan tool BCM Ctsy. Lamp Actv. Reason parameter while turning the interior lamp defeat switch ON and OFF. The reading should change between Off and Manual Defeat.

⇒	If the Ctsy. Lamp Actv. Reason parameter does not change between Off and Manual, refer to Dome/Interior Lamp Malfunction.

3. Ignition ON, Observe the Driver and Passenger Door Open Switch with a scan tool. The reading should change between Door Open and Door Closed

⇒	If the Driver and Passenger Door Open Switch parameter does not change between Door Open and Door Closed, refer to Door Open Switch Malfunction.

4. Open and close the left rear and right rear doors. The courtesy lamps should turn ON and OFF as the door is opened and closed..

⇒	If the courtesy lamps do not turn ON and OFF, refer to Door Ajar Indicator Malfunction.

5. Command the switch ON and OFF at the inoperative courtesy/reading lamp. The reading lamps should turn ON and OFF.

⇒	If the lamp does not turn ON and OFF, refer to Reading Lamps Malfunction.

6. Ignition On, fold down the sun visors and verify the vanity lamps illuminate.

⇒	If the vanity mirrors do not illuminate, refer to Vanity Mirror Malfunction.

Courtesy Lamp Malfunction

1. Ignition OFF, disconnect the harness connector at the inoperative lamp.
2. Test for less than 5 ohms between the ground circuit terminal B and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the control circuit terminal listed below and ground.

•	Overhead Console Courtesy/Reading Lamp terminal C

•	Courtesy/Reading Lamp terminal A

•	Door Courtesy Lamp terminal A

4. Ignition ON, command the Courtesy Lamps output control ON and OFF with the scan tool. The test lamp should turn ON and OFF.

⇒	If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

⇒	If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the inoperative lamp.

Dome/Interior Lamp Malfunction

1. Ignition OFF, disconnect the harness connector at the headlamp and panel dimmer switch.
2. Test for less than 5 ohms between the ground circuit terminal 8 and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify the scan tool Ctsy. Lamp Actv. Reason parameter is Off.

⇒	If the parameter is Manual or Manual Defeat, test the affected signal circuit terminal for a short to ground. If the circuit tests normal, replace the BCM.

•	Manual terminal 12

•	Manual Defeat terminal 9

4. Install a 3A fused jumper wire between the signal circuit terminal 12 and the ground circuit terminal 8. Verify the scan tool Ctsy. Lamp Actv. Reason parameter is Manual.

⇒	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 BCM.

5. Install a 3A fused jumper wire between the signal circuit terminal 9 and the ground circuit terminal 8. Verify the scan tool Ctsy. Lamp Actv. Reason parameter is Manual Defeat.

⇒	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 BCM.

6. If all circuits test normal, test or replace the headlamp and panel dimmer switch.

Reading Lamps Malfunction

1. Ignition OFF, disconnect the harness connector at the inoperative courtesy/reading lamp.
2. Test for less than 5 ohms between the ground circuit terminal B and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the appropriate control circuit terminal listed below and ground.

•	Overhead ConsoleCourtesy/Reading Lamp terminal A

•	Courtesy/Reading Lamp 2nd and 3rd row terminal C

⇒	If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

4. Remove the IS LPS fuse and verify the test lamp turns OFF.

⇒	If the test lamp remains illuminated, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, test or replace the inoperative reading lamp.

Vanity Mirror Lamps Malfunction

1. Ignition OFF, disconnect the harness connector at the inoperative vanity mirror.
2. Ignition OFF, scan tool OFF, doors CLOSED, interior lamps OFF, test for less than 5 ohms between the ground circuit terminal B and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

3. Ignition ON, verify a test lamp illuminates between the listed control circuit terminal and ground.

•	Left Sunshade terminal C

•	Right Sunshade terminal A

⇒	If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.

4. Remove the IS LPS fuse and verify the test lamp turns OFF.

⇒	If the test lamp remains illuminated, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.

5. If all circuits test normal, replace the inoperative vanity mirror.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.