B3802

DTC B3802

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B3802
- Park Lamps Request Circuit

Circuit/System Description

The body control module (BCM) monitors the park lamp switch signal circuit and the headlamp switch headlamps on signal circuit in order to determine when the park lamps and headlamps should be illuminated. When the headlamp switch is turned to PARK, the BCM senses that the park lamp switch signal circuit is grounded and the headlamps switch 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 HEAD, the BCM senses that the park lamp switch signal circuit and the headlamp switch headlamps on signal circuit are grounded. The BCM will then energize the park lamp relay and headlamp driver module (HDM) 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 on switch signal is active while the park lamp switch signal is inactive.

Action Taken When the DTC Sets

The park lamps will 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.

Circuit/System Verification

1. Ignition ON, observe the scan tool park lamp switch parameter. The reading should be between active and inactive while turning the park lamp switch on and off.
2. Observe the scan tool headlamp switch parameter. The reading should be between active and inactive while turning the headlamp switch on and off.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector X1 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 D for a short to ground. If the circuit tests normal, replace the BCM.

3. Install a 3A fused jumper wire between the signal circuit terminal E and the low reference circuit terminal C. Verify the scan tool park lamp 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 after completing the diagnostic procedure. Verification Tests

* Headlamp Switch Replacement