B2603

Diagnostic Chart:

Schematic:

CIRCUIT DESCRIPTION
The Body Control Module (BCM) controls the LF turn signal lamp. The BCM applies power to the LF turn signal lamp which in turns energizes the turn lamp.

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 circuit.
^ The condition above must be present for more than 0.3 seconds.

ACTION TAKEN WHEN DTC SETS
^ The BCM stores DTC B2603 in memory. The SERVICE VEHICLE SOON telltale illuminates.

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 control circuit.
^ A history DTC B2603 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.

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

TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
3. Tests for voltage at the turn signal lamp.
4. Verifies that the Body Control Module is providing B+ to the turn signal lamps.
5. Tests it ground is constantly being applied to the turn signal lamps B+ feed.