B3840
DTC B3840
Circuit Description
The body control module (BCM) monitors the activity of the park lamp relay switch with the headlamp switch in either the PARK position or the HEAD position.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B3840 Park Lamp Signal Circuit Low
Conditions for Running the DTC
Voltage supplied to the module is in the normal operating voltage range, approximately 10-16 volts.
Conditions for Setting the DTC
The BCM detects an open or a short to ground in the park lamp supply voltage circuit with the headlamp switch in either the PARK position or the HEAD position.
Action Taken When the DTC Sets
The BCM stores DTC B3840 in memory.
Conditions for Clearing the MIL/DTC
* A current DTC B3840 clears if the BCM no longer detects an open or a short to ground.
* A history DTC B3840 clears after 100 consecutive ignition cycles.
* The BCM receives the clear code command from the scan tool.
Diagnostic Aids
* If the DTC B3840 is a history DTC, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections. Component Tests and General Diagnostics
* An intermittent open or short to ground in the following locations may cause an intermittent malfunction to occur:
- The park lamp supply voltage circuit
- The park lamp relay
- The BCM
TEST
