Reading Lamps Malfunction

Reading 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.



Circuit/System Description

The inadvertent power supply voltage circuit of the body control module (BCM) provides battery positive voltage to the reading lamps. The reading lamps and switch are integral to the courtesy/reading lamp assembly. When the switch is closed, voltage is supplied and the lamp illuminates.


Reference Information
Schematic Reference

Interior Lights Schematics (Interior Lights Schematics)
Connector End View Reference

Component Connector End Views (Component Connector End 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

Programming and Relearning (Programming and Relearning)for scan tool information


Circuit/System Verification

Ignition ON, turn the reading lamps on and off. The reading lamps should turn on and off.


Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at an affected courtesy/reading lamp center.
2. Test for less than 1 ohm of resistance 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 listed inadvertent power supply circuit terminal and ground.

* Front terminal A
* 2nd and 3rd row terminal C


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

4. Connect the harness connector at the courtesy/reading lamp center, and remove the reading lamp bulb.
5. Connect a test lamp across the bulb terminals.
6. Ignition ON, turn the reading lamp switch on and off. The test lamp should turn on and off when changing between the commanded states.

• If the test lamp is always on, replace the affected courtesy/reading lamp center.


• If the test lamp is always off, replace the affected courtesy/reading lamp center.

7. If all circuits test normal, test or replace the affected reading lamp bulb.



Repair Instructions

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

* Overhead Console Reading Lamp and Bulb Replacement (Overhead Console Reading Lamp and Bulb Replacement)
* Programming and Relearning (Programming and Relearning)for BCM replacement, programming, and setup.