Reading Lamps Malfunction
Reading Lamps Malfunction
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview)provides an overview of each diagnostic category
Circuit/System Description
The reading lamps are made up of the overhead console reading lamps (left and right) and the roof rail reading lamps (left and right). These lamps also function as courtesy lamps. Ignition voltage is supplied at all times to the reading lamp switch by the BCM via the inadvertent power courtesy lamp circuit. When the reading lamp switch is pressed, the switch is closed and voltage is supplied to the lamp, illuminating the reading lamp bulb. The reading lamp switch is part of the reading lamp assembly.
When the reading lamp switch is in the OFF position, the reading lamps function as courtesy lamps. When the courtesy lamps are commanded ON by the BCM, voltage is supplied to the lamp via the courtesy lamp supply voltage circuit.
Reference Information
Schematic Reference
Interior Lights Schematics (Interior Lights Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Interior Lighting Systems Description and Operation (Interior Lighting Systems Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning)for Scan Tool Information
Circuit/System Verification
1. Ignition ON, press each overhead console reading lamp switches. The appropriate overhead console reading lamp should illuminate.
• If the lamp does not illuminate, refer to Overhead Console Reading Lamp Circuit Malfunction.
2. Press each roof rail reading lamp switch. The appropriate roof rail reading lamp should illuminate.
• If the lamp does not illuminate, refer to Roof Rail Reading Lamp Circuit Malfunction.
Circuit/System Testing
Overhead Console Reading Lamp Circuit Malfunction
1. Ignition OFF, disconnect the X399 inline harness connector.
2. Ignition ON, verify 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.
3. Ignition OFF, connect the X399 inline harness connector. Disconnect the harness connector at the appropriate overhead console reading lamp.
4. Test for less than 10 ohms of resistance between the ground circuit terminal A and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
5. Ignition ON, overhead console reading lamp switch ON, verify a test lamp illuminates between the control circuit terminal B and ground.
• If the test lamp does not illuminate, test or replace the overhead console reading lamp switch.
6. If all circuits test normal, test or replace the overhead console reading lamp.
Roof Rail Reading Lamp Circuit Malfunction
1. Ignition OFF, disconnect the X392 (left) or X391 (right) inline harness connector.
2. Ignition ON, verify 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.
3. Ignition OFF, connect the X392 (left) or X391 (right) inline harness connector. Disconnect the harness connector at the appropriate roof rail reading lamp.
4. Test for less than 10 ohms of resistance between the ground circuit terminal A and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
5. Ignition ON, roof rail reading lamp switch ON, verify a test lamp illuminates between the control circuit terminal B and ground.
• If the test lamp does not illuminate, test or replace the roof rail reading lamp switch.
6. If all circuits test normal, test or replace the roof rail reading lamp.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Overhead Console Courtesy Lamp Replacement (Overhead Console Courtesy Lamp Replacement)
* Roof Side Rail Lamp Replacement (Service and Repair)
* Control Module References (Programming and Relearning)for BCM replacement, setup, and programming