B2585

DTC B2585

CIRCUIT DESCRIPTION
When the body control module (BCM) receives a ground signal from the headlamp switch commanding to illuminate the park lamps, the BCM will energize the park lamp relay by grounding the park lamp relay control circuit.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC B2585 (Left or generic) Park Lamp Control Circuit

CONDITIONS FOR RUNNING THE DTC
The battery voltage must be between 9.0-16.0 volts.

CONDITIONS FOR SETTING THE DTC
- When the park lamp relay control circuit is open or shorted to ground.
- When the BCM receives a park lamp ON command and the park lamp relay control circuit is shorted to voltage.
- When the park lamp relay coil side is open or the battery positive voltage to the low beam relay is open.

ACTION TAKEN WHEN THE DTC SETS
The park lamps will not operate or will remain always on.

CONDITIONS FOR CLEARING THE MIL/DTC
- This DTC will clear on current status after the condition for setting the fault is corrected.
- A history DTC will clear after 100 consecutive ignition cycles without a fault present.
- History and current DTCs can be cleared using a scan tool.

TEST DESCRIPTION

Steps 1-13:

The numbers below refer to the step numbers on the diagnostic table.
2. Listen for an audible click when the park lamp relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
3. This step tests for voltage at the coil side of the park lamp relay.
4. This step verifies that the BCM is providing ground to the park lamp relay.
5. This step tests if ground is constantly being applied to the park lamp relay.
6. This step tests if there is opposing voltage present or an open park lamp relay control circuit.
12. After replacement of the BCM you must calibrate the new module for proper operation.