Buick Regal: DTC B3410 or B3420
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
Headlamp Leveling Control Module Front Axle Sensor Signal Circuit Short to
Ground
DTC B3410 05
Headlamp Leveling Control Module Front Axle Sensor Signal Circuit High
Voltage/Open
DTC B3410 08
Headlamp Leveling Control Module Front Axle Sensor Signal Circuit Performance
- Signal
Invalid
DTC B3420 02
Automatic Headlamp Leveling Control Module Rear Axle Sensor Signal Circuit
Short to Ground
DTC B3410 05
Headlamp Leveling Control Module Rear Axle Sensor Signal Circuit High
Voltage/Open
DTC B3420 08
Headlamp Leveling Control Module Rear Axle Sensor Signal Circuit Performance
- Signal
Invalid
Diagnostic Fault Information
1. Headlamp Leveling Malfunction
Circuit/System Description
Each headlamp assembly contains a headlamp leveling motor that is controlled
by the headlamp control
module. The front and rear suspension position sensors provide the headlamp
control module with
suspension position information. Each sensor receives a 5 V reference, signal,
and low reference circuits
from the headlamp control module. The sensors are connected to the control arms
of the front and rear
suspension. As the vehicle travels, the suspension compresses and rebounds
moving the suspension
position sensor arms. This causes the signal output of the sensor to change. The
headlamp control
module compares the information from both suspension position sensors and
adjusts the headlamp
leveling as needed.
Conditions for Running the DTC
- Battery voltage must be between 9 - 16 V.
- Engine RUNNING.
- Headlamps ON.
Conditions for Setting the DTC
B3410 02 or B3420 02
The DTC will set when the headlamp control module detects no signal and low
voltage on the sensor
signal line.
Actions Taken When the DTC Sets
- The headlamp control module disables the headlamp leveling system.
- The driver information center will display AFL Lamps Need Service.
- On vehicles equipped with both AFL and headlamp leveling, the AFL system
will remain active.
Conditions for Clearing the DTC
- The condition responsible for setting the DTC no longer exists.
- A history DTC will clear once 50 consecutive malfunction-free ignition
cycles have occurred.
Reference Information
Schematic Reference
Headlights/Daytime Running Lights (DRL) Wiring Schematics
Connector End View Reference
COMPONENT CONNECTOR END VIEWS - INDEX
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
NOTE: When replacing a headlamp leveling sensor it is necessary to
perform the Suspension Position Sensor Calibration.
1. Ignition OFF, disconnect the harness connector at the appropriate B51
Suspension Height Sensor,
ignition ON.
2. Verify a test lamp illuminates between the low reference circuit terminal 2
and B+.
- If the test lamp does not illuminate
- Ignition OFF, disconnect the harness connector at the K26 Headlamp
Control Module.
- Test for less than 2 Ω in the low reference circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K26 Headlamp Control Module.
- Go to next step: If the test lamp illuminates
3. Ignition ON.
4. Test for 4.8 - 5.2 V between the 5 V reference circuit terminal 1 and ground.
- Ignition OFF, disconnect the harness connector at the K26 Headlamp
Control Module.
- Test for infinite resistance between the 5 V reference circuit and
ground.
- If less than infinite resistance, repair the short to ground on the
circuit.
- Go to next step: If infinite resistance
- Test for less than 2 Ω in the 5 V reference circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K26 Headlamp Control Module.
- Ignition OFF, disconnect the harness connector at the K26 Headlamp
Control Module,
ignition ON.
- Test for less than 1 V between the 5 V reference circuit and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K26 Headlamp Control Module.
- Go to next step: If between 4.8 - 5.2 V
5. Verify the appropriate scan tool Leveling Position Sensor Signal parameter
is less than 5 %.
- Ignition OFF, disconnect the harness connector at the K26 Headlamp
Control Module,
ignition ON.
- Test for less than 1 V between the signal circuit terminal 3 and ground.
- If 1 V or greater, repair the short to voltage on the circuit.
- If less than 1 V, replace the K26 Headlamp Control Module.
- Go to next step: If less than 5 %
6. Install a 3 A fused jumper wire between the 5 V reference circuit terminal
1 and the signal circuit
terminal 3.
7. Engine RUNNING, verify the appropriate scan tool Leveling Position Sensor
Signal parameter is
greater than 90 %.
- Ignition OFF, disconnect the harness connector at the K26 Headlamp
Control Module.
- Test for infinite resistance between the signal circuit and ground.
- If less than infinite resistance, repair the short to ground on the
circuit.
- Go to next step: If infinite resistance
- Test for less than 2 Ω in the signal circuit end to end.
- If 2 Ω or greater, repair the open/high resistance in the circuit.
- If less than 2 Ω, replace the K26 Headlamp Control Module.
- Go to next step: If 90 % or greater
8. Test or replace the appropriate B51 Suspension Height Sensor.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.
- Suspension Position Sensor Calibration
- Control Module References for headlamp control module replacement,
programming, and setup
READ NEXT:
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.
Diag
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.
Diag
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.
Diag
SEE MORE:
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.
Diagnostic Fault
Special Tools
CH-804 Drive Axle Boot Clamp Pliers
Equivalent regional tools:Special Tools
Removal Procedure
1.
Intermediate Steering Shaft Inner Boot(1) - Remove.
2. Remove the front tire and wheel assembly.
3.
Cut the intermediate steering shaft outer boot clamp (1).
DISCARD the clamp.
4.
Sl