B2603

CIRCUIT DESCRIPTION
The Body Control Module (BCM) illuminates LF turn signal lamp during Daytime Running Lamps operation in the day mode. The BCM applies steady power to the LF turn signal lamp which illuminates the LF turn lamp in a non flashing mode.

CONDITIONS FOR RUNNING THE DTC
The BCM must be commanding the LF turn signal lamp on.

CONDITIONS FOR SETTING THE DTC
^ The BCM detects a short to battery in the LF turn signal lamp supply voltage circuit or the LF turn signal switch signal circuit.
^ The condition above must be present for more than 20 seconds.

ACTION TAKEN WHEN THE DTC SETS
The BCM stores DTC B2603 in memory.

CONDITIONS FOR CLEARING THE DTC
^ A current DTC B2603 will clear if the BCM no longer detects a short to battery in LF turn signal lamp supply voltage circuit or the LF turn signal switch signal circuit.
^ A history DTC B2603 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
^ The BCM receives a clear code command from the scan tool.

DIAGNOSTIC AIDS
^ If the DTC B2603 is a history DTC, the fault may be intermittent. Refer to Testing for Intermittent and Poor Connections in Diagrams.
^ The following conditions may cause an intermittent malfunction to occur:
- An intermittent short to battery in the LF turn signal lamp supply voltage circuit or the LF turn signal switch signal circuit
- The BCM is intermittently shorted to battery.

TEST DESCRIPTION

Steps 1-7:

The number(s) below refer to the step number(s) on the diagnostic table.
3. Tests for voltage at the turn signal lamp.
4. Test the turn signal supply voltage circuit for a short to voltage.
5. Test the turn signal switch signal circuit for a short to voltage.