B3801

DTC B3801

Circuit Description
The body control module (BCM) monitors the courtesy lamp switch signal circuit in order to determine when the courtesy/dome lamps should be illuminated. When the BCM senses that the courtesy lamp switch signal circuit is grounded when the switch is activated, the BCM will directly illuminate the courtesy/dome lamps.

Conditions for Running the DTC
- The BCM instrument panel dimmer switch reference voltage must be between 4.5-5.5 volts.
- The battery voltage must be between 9.0-16.0 volts.

Conditions for Setting the DTC
- When the instrument panel dimmer switch signal is greater than 1 volt.
- When the BCM receives a courtesy lamp ON request signal from the courtesy lamp switch.

Action Taken When the DTC Sets
The courtesy/dome lamps will not operate.

Conditions for Clearing the MIL/DTC
- This DTC will clear on current status after the condition for setting the fault is corrected.
- A history DTC will clear after 100 consecutive ignition cycles without a fault present.
- History and current DTC(s) can be cleared using a scan tool.

Diagnostic Aids
- Test the courtesy lamp switch for sticking in the ON position.
- Perform a visual inspection for loose or poor connections at all related components. Refer to Diagnostic Aids for Circuit Testing and Wiring Repair procedures.

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