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 Descriptors

DTC B3410 02: AHLD Front Axle Sensor Signal Circuit Short to Ground

DTC B3410 03: AHLD Front Axle Sensor Signal Circuit Voltage Below Threshold

DTC B3410 07: AHLD Front Axle Sensor Signal Circuit Voltage Above Threshold

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Headlamp Leveling Module B+

1

1

--

--

Suspension Position Sensor - Front Voltage Reference

B3410 02, 2

B3410 03, 2

B3410 07, 2

--

Suspension Position Sensor - Rear Voltage Reference

B3420 02, 3

B3420 03, 3

B3420 07, 3

--

Suspension Position Sensor - Front Signal

B3410 02, 2

B3410 03, 2

B3410 07, 2

--

Suspension Position Sensor - Rear Signal

B3420 02, 3

B3420 03, 3

B3420 07, 3

--

Headlamp Leveling Motor (1) Control - Left

B2667 02

B2667 05

B2667 05

--

Headlamp Leveling Motor (2) Control - Left

B2672 02

B2672 05

B2672 05

--

Headlamp Leveling Motor (3) Control - Left

B1457 02

B1457 05

B1457 05

--

Headlamp Leveling Motor (4) Control - Left

B1458 02

B1458 05

B1458 05

--

Headlamp Leveling Motor (1) Control - Right

B2677 02

B2677 05

B2677 05

--

Headlamp Leveling Motor (2) Control - Right

B2682 02

B2682 05

B2682 05

--

Headlamp Leveling Motor (3) Control - Right

B1459 02

B1459 05

B1459 05

--

Headlamp Leveling Motor (4) Control - Right

B1460 02

B1460 05

B1460 05

--

Headlamp Leveling Motor - Left Low Reference

--

1

--

--

Headlamp Leveling Motor - Right Low Reference

--

1

--

--

Suspension Position Sensor - Front Low Reference

--

2

--

--

Suspension Position Sensor - Rear Low Reference

--

3

--

--

Headlamp Leveling Actuator - Left Ground

--

1

--

--

Headlamp Leveling Actuator - Right Ground

--

1

--

--

Headlamp Leveling Module Ground

--

1

--

--

1. Headlamp Leveling Malfunction

2. Suspension Position Sensor Malfunction - Front

3. Suspension Position Sensor Malfunction - Rear

Circuit Description

The front suspension position sensor provides the headlamp level controller with front suspension position information. The sensor is permanently grounded and has voltage supplied with the ignition in the ON or CRANK position. The sensor arm is connected to the control arm of the front suspension. As the vehicle travels, the suspension compresses and rebounds moving the suspension position sensor arm. This causes the signal output of the sensor to change. The headlamp level controller compares this information with the rear suspension position sensor information and adjusts the headlamp leveling as needed.

Conditions for Running the DTC

The headlamp leveling module performs this diagnostic test mode every 3.2 millisecond when the following conditions are met:

    • The ignition is in the ON or CRANK position.
    • The headlamps are ON.

Conditions for Setting the DTC

DTC B3410 will set when one of the following conditions occur:

B3410 02

The front suspension position sensor voltage reference is less than 4.49 volts for 9.6 milliseconds.

B3410 03

The front suspension position sensor voltage reference is less than 0.5 volt for 9.6 milliseconds.

B3410 07

The front suspension position sensor voltage reference is 4.5 volts or greater for 9.6 milliseconds.

Actions Taken When the DTC Sets

B3410 02

    • The headlamp level controller will turn OFF power to the front suspension position sensor and wait 10 seconds before reapplying power to the sensor. If the reference voltage is less than 4.49 volts, the headlamp level controller will conclude a front suspension position sensor failure has occurred.
    • The headlamp level controller will disable the front suspension position sensor.

B3410 03 and B3410 07

    • If the headlamp leveling actuator has positioned the headlamps above the nominal level, the headlamp level controller will drive the headlamps to the nominal setting.
    • If the headlamp leveling actuator has positioned the headlamps below the nominal level, the headlamp level controller will disable the headlamp leveling actuator and maintain the lower than nominal level.

Conditions for Clearing the DTC

    • The condition responsible for setting the DTC no longer exists.
    • A history DTC will clear once 40 consecutive malfunction free ignition cycles have occurred.

Diagnostic Aids

Important: When one of the suspension position sensor voltage reference or sensor signal circuits are shorted to ground, it may not possible to determine which suspension position sensor voltage reference or sensor signal circuits, front or rear, has failed. If this condition occurs, all suspension position sensor voltage reference and sensor signal circuits will have to be tested for a short to ground.

Reference Information

Schematic Reference

Headlight Leveling 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

  1. Ignition OFF, disconnect the harness connector at the LF suspension position sensor.
  2. Ignition OFF, verify that a test lamp illuminates between B+ and the low reference circuit terminal C.
  3. If the test lamp does not illuminate, test the low reference circuit for an open/high resistance.
  4. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal A and ground.
  5. If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the headlamp leveling module.
    If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the headlamp leveling module.
  6. Verify the scan tool Front Leveling Position Sensor parameter is less than 0.5 volts.
  7. If greater than the specified range, test the signal circuit terminal B for a short to voltage. If the circuit tests normal, replace the headlamp leveling module.
  8. Install a 3A fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal A. Verify the scan tool Front Leveling Position Sensor parameter is greater than 4.49 volts.
  9. If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the headlamp leveling module.
  10. If all circuits test normal, test or replace the LF suspension position sensor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Headlamp Leveling Front Suspension Height Sensor Replacement
    •  Control Module References for headlamp leveling module replacement, setup, and programming