B3949
DTC B3949
Circuit Description
When the turn signal switch is placed in the right turn position, the body control module (BCM) cycles positive voltage ON and OFF to the RF turn signal lamp through the right front turn signal lamp supply voltage circuit. The front turn signal lamps illuminate steady for daytime running lamps (DRL) operation.
DTC Descriptor
This diagnostic procedure supports the following DTC:
DTC B3949 Right Front Turn Signal Circuit
Conditions for Running the DTC
* The battery voltage must be between 9-16 volts.
* Ignition switch is in the RUN position.
* Turn signal switch is placed in the right turn position.
Conditions for Setting the DTC
* An open in the right turn signal lamp supply voltage circuit is present for longer than 0.1 second.
* An open RF turn signal bulb
* An open in the ground circuit of the lamp
* An open or short to ground in the battery positive voltage circuit from the STOP/TURN 20 amp fuse in the instrument panel (I/P) fuse block
Action Taken When the DTC Sets
The right front turn signal lamp and DRL does not work.
Conditions for Clearing the DTC
* The DTC will clear on current status after the condition for setting the fault is corrected.
* A history code will clear after 100 consecutive ignition cycles without a fault present.
* History and current DTCs can be cleared using a scan tool.
Diagnostic Aids
* An open or short to ground in the battery positive voltage circuit of the STOP/TURN 20 amp fuse will cause all 4 turn signal DTCs.
* Check the RF turn lamp bulb. If the bulb is open, DTC B3948 will be set.
* If the DTC is a history DTC, the fault may be interment. refer to Testing for Intermittent Conditions and Poor Connections. Component Tests and General Diagnostics
* An interment short to ground or an open in the following locations may cause an intermittent malfunction to occur:
- The BCM
- The underhood electrical center
- The right front turn signal lamp supply voltage circuit
Test
