B3802

DTC B3802

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.

DTC Descriptor
DTC B3802 00
- Park Lamps Request Circuit

Diagnostic Fault Information





Circuit/System Description

The body control module (BCM) monitors the park lamp switch signal circuit and the headlamp switch signal circuit in order to determine when the park lamps and headlamps should be illuminated. When the headlamp switch is turned to park lamps on position, the BCM senses that the park lamp switch signal circuit is grounded and the headlamps on signal circuit is open. The BCM will then energize the park lamp relay illuminating the park lamps. When the headlamp switch is turned to the headlamps on position, the BCM senses that the park lamp switch signal and the headlamp switch signal circuits are grounded. The BCM will then energize the park lamp relay and the low or high beam headlamp relay illuminating the park lamps and headlamps.

Conditions for Running the DTC

The battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

The BCM detects the headlamp switch signal is active while the park lamp switch signal is inactive.

Action Taken When the DTC Sets

The park lamps will be inoperative or the headlamps will illuminate without the park lamps.

Conditions for Clearing the 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.

Reference Information
Schematic Reference

Headlights/Daytime Running Lights (DRL) Schematics (Headlights/Daytime Running Lights (DRL) Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Exterior Lighting Systems Description and Operation (Exterior Lighting Systems Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector X3 at the headlamp switch.
2. Ignition ON, verify the scan tool Headlamp Switch parameter is Inactive.

• If not the specified value, test the signal circuit terminal L for a short to ground. If the circuit tests normal, replace the BCM.

3. Install a 3A fused jumper wire between the park switch signal circuit terminal M and the low reference circuit terminal K. Verify the scan tool Parklamp Switch parameter is Active.

• If not the specified value, test the signal circuit for an open/high resistance. If the circuit tests normal, replace the BCM.

4. If all circuits test normal, test or replace the headlamp switch.

Repair Instructions

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

* Turn Signal Multifunction Switch Replacement (Turn Signal Multifunction Switch Replacement)
* Control Module References (Programming and Relearning) for BCM replacement, programming, and setup