B2580

DTC B2580

CIRCUIT DESCRIPTION
hen the body control module (BCM) receives a ground signal from the multifunction high beam or flash to pass (FTP) switch commanding to illuminate the high beam headlamps, the BCM will energize the high beam relay by grounding the high beam relay control circuit.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC B2580 (Left or generic) Headlamp High Beam Control Circuit

CONDITIONS FOR RUNNING THE DTC
The battery voltage must be between 9-16 volts.

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

ACTION TAKEN WHEN THE DTC SETS
The high beam headlamps 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

Step 1 - Step 13:

The numbers below refer to the step numbers on the diagnostic table.
2. Listen for an audible click when the high beam 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 high beam relay.
4. This step verifies that the BCM is providing ground to the high beam relay.
5. This step tests if ground is constantly being applied to the high beam relay.
6. This step tests if there is opposing voltage present or an open high beam relay control circuit, including the relay coil side.
12. After replacement of the BCM you must calibrate the new module for proper operation.