B2575

Diagnostic Trouble Code Chart (Part 1 Of 2):

Diagnostic Trouble Code Chart (Part 2 Of 2):

Wiring Schematic:

CIRCUIT DESCRIPTION
This circuit controls the ALC Relay coil by grounding the circuit through the Body Function Controller (BFC). This is a trouble code (both current and history) that indicates the Headlamps were not ON when the ALC Relay output was ON.

CONDITIONS FOR SELLING THE DTC
All of the following conditions must he met:
^ The ALC option is enabled and Ignition 1 active.
^ The ALC Headlamp output is active.
^ The High Beams are not ON (i.e. are OFF or in DRL mode).
^ The Low Beams are OFF for 5 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ Stores DTC B2575 in the Body Function Controller (BFC) memory.
^ The SERVICE VEHICLE SOON indicator will illuminate.

CONDITIONS FOR CLEARING THE DTC
^ The Body Function Controller reads the proper Headlamp voltage.
^ Conditions for the fault are no longer present.
^ Use the scan tool.

DIAGNOSTIC AIDS
^ Turn the Ignition Switch to the RUN position, cover the Ambient Light Sensor on the dash and wait for 30 seconds. The Low Beams should illuminate. If the Low Beams do not illuminate refer to Headlight: Daytime Running Lights, Cell 102, in Wiring Diagrams. Diagrams
^ Turn the Ignition Switch to the RUN position, activate the High Beams and cover the Ambient Light Sensor on the dash then wait for 30 seconds. The High Beams should illuminate. If the High Beams do not illuminate refer to Headlight: Daytime Running Lights. Lighting and Horns
^ When the diagnostics direct you to take electrical measurements at the Wiring Harness Junction Blocks, refer to Power Distribution, Cell 10, in Electrical Diagnosis, for terminal assignments of the Wiring Harness Junction Blocks. Diagrams
^ If the DTC is a history DTC, the problem may be intermittent. Try performing the tests shown while wiggling wiring and connectors, this can often cause the malfunction to appear

TEST DESCRIPTION
The numbers below refer to the numbers on the diagnostic table.
4. This step determines if the Body Function Controller (BFC) is reading that the Low Beam Headlamps are working properly.
6. This step determines if the Body Function Controller (BFC) is reading that the High Beam Headlamps are working properly.
8. This step determines if the DRL Relay is functioning properly.
9. This step determines if the ALC Relay is functioning properly.