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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

Battery voltage for the courtesy lamps is supplied at all times to the body control module (BCM). When the BCM receives a signal to command the courtesy lamps ON, it then applies voltage through the dome/courtesy lamps control circuit to the courtesy lamps.

Reference Information
Schematic Reference

Interior Lights Schematics (Interior Lights 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 Switch parameter while opening and closing each vehicle door. The parameter should change between Inactive and Active.

• 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 Switch parameter while opening and closing the rear liftgtate. The parameter should change between Active and Inactive.

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

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

• If one or more courtesy lamps do not turn ON and OFF when changing between the commanded states, refer to Courtesy Lamp Malfunction.

4. Cycle the Dome/Reading Lamps switch in all positions while observing the scan tool Dome Lamp Switch parameter. The parameter should change between Inactive and Active.

• If the parameter does not change, refer to Dome Lamp Switch Malfunction.

5. Command the Courtesy Lamps Duty Cycle Command ON and OFF with a scan tool. The reading lamps should turn ON and OFF while changing between the commanded states.

• If the reading lamps do not turn ON and OFF when changing between the commanded states, refer to Reading Lamp Malfunction.

6. Turn the center console compartment lamp ON and OFF by using the center console compartment lamp switch. The center console compartment lamp should turn ON and OFF while changing between the selected states.

• If the center console compartment lamp does not turn ON and OFF when changing between the selected states, refer to Center Console Illumination Malfunction.

7. Turn the sunshade lamp ON and OFF by using the sunshade lamp switch. The sunshade lamp should turn ON and OFF while changing between the selected states.

• If the sunshade lamp does not turn ON and OFF when changing between the selected states, refer to Sunshade Illumination Malfunction.

Circuit/System Testing

Courtesy Lamp Malfunction
1. Disconnect the harness connector at the appropriate courtesy lamp.
2. 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:

* E8 Instrument Panel Courtesy Lamp - terminal 2
* E37 Dome/Reading Lamp Middle - terminal 6
* E37 Dome/Reading Lamp Rear - terminal 6
* E37 Dome/Reading Lamp Front - terminal B

• 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:

* E8 Instrument Panel Courtesy Lamp - terminal 1
* E37 Dome/Reading Lamp Middle - terminal 2
* E37 Dome/Reading Lamp Rear - terminal 2
* E37 Dome/Reading Lamp Front - terminal A

4. Command the Courtesy Lamps Duty Cycle Command 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 K9 BCM.
• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.

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

Dome Lamp Switch Malfunction
1. Ignition OFF, disconnect the harness connector at the S12 dome lamp switch.
2. Scan tool disconnected, doors CLOSED, interior lamps OFF, test for less than 5 ohm between the ground circuit terminal 1 and ground.

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

3. Ignition ON, verify the scan tool Interior/Courtesy Lighting Master Switch parameter is Inactive.

• If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the K9 BCM.

4. Verify the scan tool Dome Lamp Switch parameter is Inactive.

• If not the specified value, test the signal circuit terminal 3 for a short to ground. If the circuit tests normal, replace the K9 BCM.

5. Connect a 3 A fused jumper wire between the signal circuit terminal 2 and ground. Verify the scan tool Interior/Courtesy Lighting Master Switch parameter is Active.

• If not the specified value, test the signal circuit for a short to B+ or an open/high resistance. If the circuit tests normal, replace the K9 BCM.

6. Connect a 3 A fused jumper wire between the signal circuit terminal 3 and ground. Verify the scan tool Dome Lamp Switch parameter is Active.

• If not the specified value, test the signal circuit for a short to B+ or an open/high resistance. If the circuit tests normal, replace the K9 BCM.

7. If all circuits test normal, replace the S12 dome lamp switch.

Reading Lamp Malfunction
1. Ignition OFF, disconnect the harness connector at the E37 dome/reading lamp - front.
2. Test for less than 5 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. Ignition ON, turn the dome/reading lamp ON and OFF with the S17 dome/reading lamp switch. The test lamp should turn ON and OFF when changing between the selected 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 K9 BCM.
• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 BCM.

5. If all circuits test normal, test or replace the E37 dome/reading lamp - front.

Center Console Illumination Malfunction
1. Ignition OFF, disconnect the harness connector at the E28 center console compartment lamp.
2. Test for less than 5 ohm between the ground circuit terminal 2 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 1 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 K9 BCM.

4. If all circuits test normal, tests or replace the E28 center console compartment lamp.

Sunshade Illumination Malfunction
1. Ignition OFF, disconnect the harness connector at the A3 sunshade.
2. Test for less than 5 ohm between the ground circuit terminal B and ground.

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

3. Connect a test lamp between the control circuit terminal A and ground.
4. Turn the sunshade lamp ON and OFF with the sunshade switch. The test lamp should turn ON and OFF when changing between the selected 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 K9 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 K9 BCM.

5. If all circuits test normal, test or replace the A3 sunshade.

Repair Instructions

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

* Dome and Reading Lamp Switch Replacement (Dome and Reading Lamp Switch Replacement)
* Refer to the appropriate replacement procedure for the lighting component that requires replacement.
* Control Module References (Programming and Relearning) for BCM replacement, setup, and programming

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