B3410

DTC B3410 or B3420

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.



DTC Descriptors
DTC B3410 01
- AHLD Front Axle Sensor Signal Circuit Short to Battery

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

DTC B3420 01
- AHLD Rear Axle Sensor Signal Circuit Short to Battery

DTC B3420 02
- AHLD Rear Axle Sensor Signal Circuit Short to Ground

DTC B3420 03
- AHLD Rear Axle Sensor Signal Circuit Voltage Below Threshold

DTC B3420 07
- AHLD Rear Axle Sensor Signal Circuit Voltage Above Threshold




Diagnostic Fault Information






Circuit/System Description

The front and rear suspension position sensors provide the headlamp control module with front and rear suspension position information. Each sensor receives a 5-volt reference, signal, and low reference circuits from the headlamp control module. The sensor are connected to the control arms at 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 sensors to change. The headlamp control module compares the information from the front and rear suspension position sensors and adjusts the headlamp leveling as needed.


Conditions for Running the DTC

* Battery voltage must be between 9-16 volts.
* The ignition is in the ON or RUN position.
* The headlamps are ON.



Conditions for Setting the DTC

B3410 01 or B3420 01

The DTC will set when the headlamp control module detects a short to voltage or an open/high resistance on the 5-volt reference circuit.

B3410 02 or B3420 02

The DTC will set when the headlamp control module detects a short to ground on the 5-volt reference circuit.

B3410 03 or B3420 03

The DTC will set when the headlamp control module detects a short to ground or an open/high resistance on the sensor signal circuit.

B3410 07 or B3420 07

The DTC will set when the headlamp control module detects a short to voltage on the sensor signal circuit.


Actions Taken When the DTC Sets

* The headlamp control module disables the headlamp leveling system.
* The driver information center (DIC) 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 cycles have occurred.



Reference Information
Schematic Reference

Headlight Leveling Schematics (Headlight Leveling Schematics)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Exterior Lighting Systems Description and Operation (Exterior Lighting Systems Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) for scan tool information


Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate headlamp leveling sensor.
2. Ignition OFF, test for less than 10.0 ohms between the low reference circuit terminal C and ground.

• If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the headlamp control module.

3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal A and ground.

• 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 control 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 control module.

4. Verify the appropriate scan tool leveling position sensor parameter is less than 0.5 volt.

• 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 control module.

5. Install a 3A fused jumper wire between the signal circuit terminal B and the 5-volt reference circuit terminal A. Verify the appropriate scan tool leveling position sensor parameter is greater than 4.8 volts.

• 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 control module.

6. If all circuits test normal, replace the appropriate headlamp leveling sensor.



Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Headlamp Leveling Front Suspension Height Sensor Replacement (Headlamp Leveling Front Suspension Height Sensor Replacement)
* Headlamp Leveling Rear Suspension Height Sensor Replacement (Headlamp Leveling Rear Suspension Height Sensor Replacement)
* Control Module References (Programming and Relearning) for headlamp control module replacement, setup, and programming