The headlamp leveling sensor front provides the headlamp leveling control modules with front axle position information. The headlamp leveling switch bit 1 signal circuit is shared between the 2 headlamp leveling control modules. The sensor is permanently grounded and has battery voltage supplied with the ignition in the ON 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 headlamp leveling sensor front arm. This causes the signal output of the sensor to change. The headlamp leveling control module then compare this information with the headlamp leveling sensor rear information and adjusts the headlamp leveling accordingly.
This diagnostic procedure supports the following DTC:
DTC B3410 AHLD Front Axle Sensor Signal Circuit
Each of the headlamp leveling control modules run the DTC every 40 milliseconds when the following conditions are met.
• | The ignition is ON. |
• | The headlamps are ON. |
Each time the DTC is run and a fault is detected, an internal counter in each of the headlamp leveling control modules is increased by 1. When the counter reaches 5 the DTC is set as current.
The headlamp leveling control module uses an internal offset of the headlamp leveling sensor rear in order to keep the leveling system active.
Each time the DTC is run and a fault is not detected, the counter is decreased by 1 until the counter reaches 0.
The numbers below refer to the step numbers on the diagnostic table.
This step determines the proper diagnostic path for the DTC.
This step tests for battery voltage at the headlamp leveling sensor front.
This step tests for an open in the headlamp leveling sensor front ground circuit.
This step tests for both a short to ground and a short to battery voltage.
This step tests for an open or high resistance between the headlamp leveling sensor front and the headlamp leveling control module that has the DTC present.
Step | Action | Yes | No |
---|---|---|---|
Schematic Reference: Headlight Leveling Schematics Connector End View Reference: Lighting Systems Connector End Views | |||
1 | Did you perform the Diagnostic System Check - Vehicle? | Go to Step 2 | Go to Diagnostic System Check - Vehicle in Vehicle DTC Information |
2 |
Is the DTC B3410 a current DTC? | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems |
Is the DTC B3410 current in both the right and left headlamp leveling control modules? | Go to Step 4 | Go to Step 7 | |
Does the test lamp illuminate? | Go to Step 5 | Go to Step 10 | |
Connect a test lamp between the ignition 1 voltage circuit of the headlamp leveling sensor front and the ground circuit of the headlamp leveling sensor front. Does the test lamp illuminate? | Go to Step 6 | Go to Step 11 | |
Test the headlamp leveling switch bit 1 signal circuit for an open, short to voltage, short to ground, or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 14 | Go to Step 8 | |
Test the headlamp leveling switch bit 1 signal circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 14 | Go to Step 9 | |
8 | Inspect for poor connections at the harness connector of the headlamp leveling sensor front. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 14 | Go to Step 12 |
9 | Inspect for poor connections at the harness connector of the appropriate headlamp leveling control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | Go to Step 14 | Go to Step 13 |
10 | Repair the open or high resistance in the ignition 1 voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 14 | -- |
11 | Repair the open or high resistance in the ground circuit of the headlamp leveling sensor front . Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you complete the repair? | Go to Step 14 | -- |
12 |
Important: Perform the calibration procedure for both headlamp leveling modules. Refer to Headlamp Leveling Module Programming and Setup in Programming and Setup. Replace the headlamp leveling sensor front. Refer to Headlamp Leveling Front Suspension Height Sensor Replacement . Did you complete the replacement? | Go to Step 14 | -- |
13 |
Important: Perform the calibration procedure for the appropriate headlamp leveling module. Refer to Headlamp Leveling Module Programming and Setup in Programming and Setup. Replace the appropriate headlamp leveling control module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming. Did you complete the replacement? | Go to Step 14 | -- |
14 |
Does the DTC reset? | Go to Step 2 | System OK |