Circuit Description
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 battery positive voltage.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B2618 Passenger Compartment Dimming Circuit High
Conditions for Running the DTC
Voltage supplied to the module is in the normal operating range, approximately 10-16 volts.
Conditions for Setting the DTC
| • | The BCM detects a short to voltage in the courtesy lamps supply voltage circuit of the interior lamps when the dimmer switch is in the ON position or the doors are open. |
| • | The condition is present for more than 3 ms. |
Action Taken When the DTC Sets
The BCM stores DTC B2618 in memory.
Conditions for Clearing the MIL/DTC
| • | A current DTC B2618 clears if the BCM no longer detects a short to battery positive voltage. |
| • | A history DTC B2618 clears after 100 consecutive ignition cycles. |
| • | The BCM receives the Clear Code command from the scan tool. |
Diagnostic Aids
| • | If the DTC B2618 is a history DTC, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections . |
| • | An intermittent short to voltage in the following locations may cause an intermittent malfunction to occur: |
| - | The courtesy lamps supply voltage circuit of the interior lamps |
| - | The BCM |
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: Interior Lights 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 when the instrument panel (I/P) dimmer switch is 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 and repair a short to voltage in the courtesy lamps supply voltage circuit of the interior lamps. 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 |
