GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B2582 00: Headlamp High Beam Control Circuit Low

DTC B2583 00: Headlamp High Beam Control Circuit High

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Headlamp Switch High Beam Signal

2

2

2

--

Headlamp Switch Headlamps ON Signal

3

3

3

--

Headlamp Switch Headlamps OFF Signal

3

3

3

--

Headlamp High Beam Relay Control

B2582 00

2

2583 00

--

Headlamp Low Beam Relay Control

1

1

B2575 00

--

LF High Beam Headlamp Control

2

2

2

--

LF Low Beam Headlamp Control

1

1

1

--

RF High Beam Headlamp Control

2

2

2

--

RF Low Beam Headlamp Control

1

1

1

--

LF Headlamp Ground

--

1

--

--

RF Headlamp Ground

--

1

--

--

Turn Signal/Multifunction Switch Ground

--

4

--

--

1. Headlamp Malfunction - Low Beam

2. Headlamp Malfunction - High Beam

3. Headlamp Switch Malfunction

4. Dimmer Switch Malfunction

Circuit/System Description

When 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 HI/LO BEAM relay by applying B+ to the HI/LO BEAM relay control circuit.

Conditions for Running the DTC

Battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

B2582

When the BCM receives a high beam switch on command and the front fog lamp relay control circuit is shorted to ground.

B2583

When the BCM receives a high beam switch off command and the front fog lamp relay control circuit is shorted to voltage.

Action Taken When the DTC Sets

The high beam headlamps will not operate or will remain always on.

Conditions for Clearing the 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.

Reference Information

Schematic Reference

Headlights/Daytime Running Lights (DRL) Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Exterior Lighting Systems Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

High Beam Relay Control Circuit Test

  1. Ignition OFF, disconnect the HI/LO BEAM relay.
  2. Test for less than 5 ohms between the relay ground terminal and ground.
  3. If less than the specified value, test the ground circuit for an open/high resistance.
  4. Connect a test lamp between the relay coil control circuit terminal and the ground circuit terminal.
  5. Ignition ON, operate the high beam switch ON and OFF with a scan tool. The test lamp should turn ON and OFF.
  6. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
    If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the BCM.
  7. If all circuits test normal, test or replace the relay.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Relay Replacement
    •  Control Module References for BCM replacement, programming, and setup.