B2553

CIRCUIT DESCRIPTION
The Body Control Module (BCM) controls the backup lamp relay. The BCM grounds the backup lamps relay control circuit which energizes the backup lamp relay.

CONDITIONS FOR RUNNING THE DTC
^ The transaxle must be in the reverse position
^ The Ignition switch must be in the RUN position.
^ The emergency vehicle interior lamp switch is not enabled.

CONDITIONS FOR SETTING THE DTC
^ The BCM detects a short to battery in the backup lamp relay control circuit when the BCM tries to energize the backup lamp relay.
^ The condition above must be present for more than 0.3 seconds.

ACTION TAKEN WHEN THE DTC SETS
The BCM stores DTC B2553 in memory.

CONDITIONS FOR CLEARING THE DTC
^ The BCM no longer detects a short to battery in the backup lamp relay control circuit.
^ A history DTC B2553 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 B2553 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 backup lamp relay control circuit.
- The backup lamp relay coil is intermittently shorted to the battery.
- The BCM is intermittently shorted to the battery.

TEST DESCRIPTION

Steps 1-7:

The number(s) below refer to the step number(s) on the diagnostic table.
2. Listen for an audible click when the backup lamp relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
3. Verifies that the BCM is providing ground to the backup lamp relay. Indicating a short to voltage internal to the backup lamp relay.
4. Tests for a short to voltage at control circuit of the backup lamp relay.