The body control module (BCM) controls the following lamps when the instrument panel (I/P) dimmer switch is ON or any door is opened:
| • | The I/P courtesy lamp, LH | 
| • | The I/P courtesy lamp, RH | 
| • | The inside rear view mirror lamps | 
| • | The cargo lamp | 
| • | The roof rail reading lamp, LH | 
| • | The roof rail reading lamp, RH | 
| • | The sunshade lighted vanity mirror lamps, LH | 
| • | The sunshade lighted vanity mirror lamps, RH | 
The BCM monitors all but the sunshade lighted vanity mirror lamps for a short to ground or a short to voltage.
This diagnostic procedure supports the following DTC:
DTC B2617 Passenger Compartment Dimming Circuit Low
Voltage supplied to the module is in the normal operating range, approximately 10-16 volts.
| • | The BCM detects a short to ground in the courtesy lamps supply voltage circuit of the interior lamps when the dimmer switch is in the OFF position, and the doors are not open. | 
| • | The condition is present for more than 3 ms. | 
The BCM stores DTC B2617 in memory.
| • | A current DTC B2617 clears if the BCM no longer detects a short to ground. | 
| • | A history DTC B2617 clears after 100 consecutive ignition cycles. | 
| • | The BCM receives the Clear Code command from the scan tool. | 
| • | If the DTC B2617 is a history DTC, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections . | 
| • | An intermittent short to ground in the following locations may cause an intermittent malfunction to occur: | 
| - | The courtesy lamps supply voltage circuit | 
| - | The BCM | 
Step  | Action  | Yes  | No  | 
|---|---|---|---|
Schematic Reference: Interior Lights Dimming Schematics Connector End View Reference: Master Electrical Component List  | |||
1  | Did you perform the Diagnostic System Check - Vehicle?  | Go to Step 2  | |
2  | Turn the ignition to the RUN position. Do the interior lamps illuminate with the instrument panel (I/P) dimmer switch in the ON position?  | Go to Diagnostic Aids  | Go to Step 3  | 
3  | 
 Does the test lamp illuminate?  | Go to Step 4  | Go to Step 5  | 
4  | Test for a short to ground in the courtesy lamps supply voltage circuit. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition?  | Go to Step 6  | --  | 
5  | Replace the BCM. Refer to Control Module References for replacement, setup, and programming. Did you complete the replacement?  | Go to Step 6  | --  | 
6  | 
 Does the DTC reset?  | System OK  | Go to Step 3  |