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Courtesy Lamps Malfunction




Courtesy Lamps Malfunction

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

Diagnostic Fault Information





Circuit/System Description

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, dome lamps, rearview mirror lamps, and rear compartment lamps. The BCM also provides a serial data message to the driver door module (DDM) and front passenger door module (PDM) to apply battery voltage to the door courtesy 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.

Reference Information
Schematic Reference

* Interior Lights Schematics (Interior Lights Schematics)
* Interior Lights Dimming Schematics (Interior Lights Dimming Schematics)

Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

Interior Lighting Systems Description and Operation (Interior Lighting Systems)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Verification

1. Ignition ON, observe the scan tool Door Ajar Sw. parameter while opening and closing each vehicle door. The parameter should change between Active and Inactive.

• If the parameter does not change between the selected states, refer to Door Ajar Indicator Malfunction (Door Ajar Indicator Malfunction).

2. Observe the scan tool Rear Closure Ajar Sw. parameter while opening and closing the trunk. The parameter should change between Active and Inactive.

• If the parameter does not change between the selected states, refer to Trunk Ajar Indicator Malfunction (Trunk Ajar Indicator Malfunction).

3. All doors closed, observe the scan tool Ctsy. Lamp Actv. Reason parameter while turning the dome lamp 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 Lamp Switch Malfunction.

4. Command the Courtesy Lamps ON and OFF with a scan tool. The overhead courtesy lamps should turn ON and OFF when changing between the commanded states.

• If the courtesy lamps do not turn ON and OFF when commanded, refer to Overhead Courtesy Lamp Malfunction.

5. Turn the individual reading lamps ON and OFF with their respective switches. The reading lamps should turn ON and OFF when changing between the selected states.

• If any reading lamp does not turn ON and OFF when selected, refer to Reading Lamp Malfunction.

6. Turn the left and right sunshade lamps ON and OFF with their respective switches. The sunshade lamps should turn ON and OFF when changing between the selected states.

• If any reading lamp does not turn ON and OFF when selected, refer to Sunshade Illumination Malfunction.

7. Turn the rear compartment courtesy lamp ON and OFF by opening and closing the trunk. The rear compartment courtesy lamp should turn ON and OFF when changing between the selected states.

• If the rear compartment courtesy lamp does not turn ON and OFF when selected, refer to Rear Compartment Courtesy Lamp Malfunction.

8. Turn the I/P compartment lamp ON and OFF by turning the I/P compartment lamp switch ON and OFF. The I/P compartment lamp should turn ON and OFF when changing between the selected states.

• If the I/P compartment lamp does not turn ON and OFF when selected, refer to I/P Compartment Lamp Malfunction.

9. Command the door switch Puddle/Courtesy Lamps ON and OFF with a scan tool. The front door courtesy lamps should turn ON and OFF when changing between the commanded states.

• If the front door courtesy lamps do not change between ON and OFF, refer to Door Courtesy Lamp Malfunction - Front.

10. Command the Courtesy Lamps ON and OFF with a scan tool. The rear door courtesy lamps should turn ON and OFF when changing between the commanded states.

• If the rear door courtesy lamps do not change between ON and OFF, refer to Door Courtesy Lamp Malfunction - Rear.

11. Command the Courtesy Lamps ON and OFF with a scan tool. The footwell courtesy lamps should turn ON and OFF when changing between the commanded states.

• If the footwell courtesy lamps do not change between ON and OFF, refer to Footwell Courtesy Lamp Malfunction.

12. Command the Courtesy Lamps ON and OFF with a scan tool. The cargo lamps should turn ON and OFF when changing between the commanded states.

• If the cargo lamps do not change between ON and OFF, refer to Cargo Lamp Malfunction.

Circuit/System Testing

Dome Lamp Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the I/P dimmer switch.
2. Ignition OFF, scan tool OFF, interior lamps OFF, doors CLOSED, test for less than 1.0 ohm between the ground circuit terminal 7 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 not the specified value, test the signal circuit for a short to ground. If the circuit tests normal, replace the BCM.

4. Install a 3 A fused jumper wire between the signal circuit terminal 8 and ground. 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. If all circuits test normal, test or replace the I/P dimmer switch.

Overhead Courtesy Lamp Malfunction
1. Ignition OFF, disconnect the X6 harness connector at the BCM.
2. Ignition ON, verify that a test lamp illuminates between the BCM 3 fuse B+ circuit terminal 1 and ground.

• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

3. Ignition OFF, reconnect the X6 harness connector at the BCM.
4. Disconnect the harness connector at the appropriate courtesy/reading lamp.
5. Ignition OFF, scan tool OFF, doors CLOSED, interior lamps OFF, test for less than 5.0 ohm between the ground circuit terminal listed below and ground:

* Left front courtesy lamp - terminal B
* Right front courtesy lamp - terminal B
* Left rear courtesy lamp (sedan) - terminal B
* Right rear courtesy lamp (sedan) - terminal B
* 2nd row courtesy lamp (wagon) - terminal 6

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

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

* Left front courtesy lamp - terminal A
* Right front courtesy lamp - terminal A
* Left rear courtesy lamp (sedan) - terminal A
* Right rear courtesy lamp (sedan) - terminal A
* 2nd row courtesy lamp (wagon) - terminal 2

7. Command the Courtesy Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

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

8. If all circuits test normal, replace the courtesy/reading lamp.

Reading Lamp Malfunction
1. Ignition OFF, disconnect the X3 harness connector at the BCM.
2. Ignition ON, verify that a test lamp illuminates between the BCM 2 fuse B+ circuit terminal 2 and ground.

• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.

3. Ignition OFF, reconnect the X3 harness connector at the BCM.
4. Disconnect the harness connector at the appropriate courtesy/reading lamp.
5. Ignition OFF, scan tool OFF, doors CLOSED, interior lamps OFF, test for less than 5.0 ohm between the ground circuit terminal listed below and ground:

* Left front reading lamp - terminal B
* Right front reading lamp - terminal B
* Left rear reading lamp (sedan) - terminal B
* Right rear reading lamp (sedan) - terminal B
* 2nd row reading lamp (wagon) - terminal 6

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

6. Ignition OFF, verify that a test lamp illuminates between the control circuit terminal listed below and ground:

* Left front reading lamp - terminal C
* Right front reading lamp - terminal C
* Left rear reading lamp (sedan) - terminal C
* Right rear reading lamp (sedan) - terminal C
* 2nd row reading lamp (wagon) - terminal 1

• 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.

7. Remove the BCM 2 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.

8. If all circuits test normal, replace the courtesy/reading lamp.

Sunshade Illumination Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate sunshade.
2. Ignition OFF, scan tool OFF, doors CLOSED, interior lamps OFF, test for less than 5.0 ohm 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 control circuit terminal A and ground.

• 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 BCM 2 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 sunshade.

Rear Compartment Courtesy Lamp Malfunction
1. Ignition OFF, disconnect the harness connector at the rear compartment courtesy lamp.
2. Open the trunk.
3. Ignition OFF, verify that a test lamp illuminates between B+ and the ground circuit terminal B.

• If the test lamp does not illuminate, test the ground circuit for short to voltage or an open/high resistance. If the circuit tests normal, replace the rear compartment lid latch.

4. Ignition OFF, verify that a test lamp illuminates between the control circuit terminal C and ground.

• 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.

5. Remove the BCM 2 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.

6. If all circuits test normal, replace the rear compartment courtesy lamp.

I/P Compartment Lamp Malfunction
1. Ignition OFF, disconnect the harness connector at the I/P compartment lamp.
2. Open the I/P compartment.
3. Ignition OFF, verify that a test lamp illuminates between B+ and the ground circuit terminal A.

• If the test lamp does not illuminate, test the ground circuit for an open/high resistance. If the circuit tests normal, replace the I/P compartment lamp switch.

4. Ignition OFF, verify that a test lamp illuminates between the control circuit terminal B and ground.

• 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.

5. Remove the BCM 2 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.

6. If all circuits test normal, replace the I/P compartment lamp.

Door Courtesy Lamp Malfunction - Front
1. Ignition OFF, disconnect the harness connector at the appropriate front door courtesy lamp.
2. Ignition ON, test for less than 20.0 ohm between the low reference circuit terminal B and ground.

• If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the door lock/window switch.

3. Connect a test lamp between the control circuit terminal A and the low reference circuit terminal B.
4. Command the Puddle/Courtesy Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the door lock/window switch.
• 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 door lock/window switch.

5. If all circuits test normal, test or replace the front door courtesy lamp.

Door Courtesy Lamp Malfunction - Rear
1. Ignition OFF, disconnect the harness connector at the appropriate rear door courtesy lamp.
2. Ignition OFF, verify that a test lamp illuminates between B+ and the ground circuit terminal B.

• If the test lamp does not illuminate, test the ground for an open/high resistance.

3. Connect a test lamp between the control circuit terminal A and the ground circuit terminal B.
4. Command the Courtesy Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

• 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.
• If the test lamp is always ON, 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 rear door courtesy lamp.

Footwell Courtesy Lamp Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate footwell courtesy lamp.
2. Ignition OFF, scan tool OFF, test for less than 5.0 ohm 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 A and ground.
4. Command the Courtesy Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

• 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.

5. Remove the BCM 2 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.

6. If all circuits test normal, replace the footwell courtesy lamp.

Cargo Lamp Malfunction
1. Ignition OFF, disconnect the harness connector at the appropriate cargo lamp.
2. Ignition OFF, verify that a test lamp illuminates between B+ and the ground circuit terminal B.

• If the test lamp does not illuminate, test the ground for an open/high resistance.

3. Connect a test lamp between the control circuit terminal A and the ground circuit terminal B.
4. Command the Courtesy Lamps ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.

• 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.
• If the test lamp is always ON, 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 cargo lamp.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Refer to the appropriate replacement procedure for the lighting component that requires replacement.
* Dimmer Switch Replacement (Service and Repair)
* Rear Compartment Lid Latch Replacement (Coupe) (Rear Compartment Lid Latch Replacement)Rear Compartment Lid Latch Replacement (Sedan) (Rear Compartment Lid Latch Replacement)
* Control Module References (Programming and Relearning) for BCM, driver side and passenger side door lock and side window switch replacement, setup, and programming

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