Lighting (Base)
DTC B3435 or B3440 (Base)
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 B3435 00
- AHLD Left Servo Driver Circuit
DTC B3435 02
- AHLD Left Servo Driver Circuit Short to Ground
DTC B3435 39
- AHLD Left Servo Driver Circuit Internal Electronic Failure
DTC B3435 54
- AHLD Left Servo Driver Circuit Over Temperature
DTC B3440 00
- AHLD Right Servo Driver Circuit
DTC B3440 02
- AHLD Right Servo Driver Circuit Short to Ground
DTC B3440 39
- AHLD Right Servo Driver Circuit Internal Electronic Failure
DTC B3440 54
- AHLD Right Servo Driver Circuit Over Temperature
Diagnostic Fault Information
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-volt 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. The headlamp control module is wired to each headlamp leveling motor with 4 directional motor control circuits.
Conditions for Running the DTC
* Battery voltage must be between 9-16 volts.
* Ignition in the ON or RUN position.
* Headlamps ON.
Conditions for Setting the DTC
B3435 00
The headlamp control module detects a short to voltage or an open/high resistance on any of the left motor control circuits.
B3435 02
The headlamp control module detects a short to ground on any of the left motor control circuits.
B3435 39
The headlamp control module detects an internal electronic failure.
B3435 54
The headlamp control module detects an overheating condition on any of the left motor control circuits.
B3440 00
The headlamp control module detects a short to voltage or an open/high resistance on any of the right motor control circuits.
B3440 02
The headlamp control module detects a short to ground on any of the right motor control circuits.
B3440 39
The headlamp control module detects an internal electronic failure.
B3440 54
The headlamp control module detects an overheating condition on any of the right motor control circuits.
Actions Taken When the DTC Sets
* When DTC B3435 or DTC B3440 sets, the headlamp control module will attempt to return the lamps to a nominal position and disable all requests to all headlamp actuators.
* The driver information center (DIC) will display AFL Lamps Need Service.
Conditions for Clearing the DTC
* The condition responsible for setting the DTC no longer exists and the ignition is cycled.
* 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 inoperative headlamp.
2. Remove the AFS 15A fuse.
3. Ignition OFF, scan tool OFF, test for 10 ohms -25K ohms between each control circuit terminal listed below and ground.
* Headlamp leveling motor control terminal 1
* Headlamp leveling motor control terminal 2
* Headlamp leveling motor control terminal 3
* Headlamp leveling motor control terminal 4
• If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the headlamp control module.
• If less than the specified range, test the control circuit for a short to ground. If the circuit tests normal, replace the headlamp control module.
4. Install the AFS 15A fuse.
5. Ignition ON, scan tool OFF, headlamps ON, verify that a test lamp does not illuminate between each control circuit terminal listed below and ground.
* Headlamp leveling motor control terminal 1
* Headlamp leveling motor control terminal 2
* Headlamp leveling motor control terminal 3
* Headlamp leveling motor control terminal 4
• If the test lamp illuminates, test the control circuit for a short to voltage. If the circuit tests normal, replace the headlamp control module.
6. If all circuits test normal, replace the appropriate headlamp assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Headlamp Assembly or Headlamp Bulb and/or Cornering, Sidemarker, Park, Turn Signal Bulb Replacement (TT6) (Service and Repair)Headlamp Assembly or Headlamp Bulb and/or Cornering, Sidemarker, Park, Turn Signal Bulb Replacement (TT7) (Service and Repair)Headlamp Assembly or Headlamp Bulb and/or Cornering, Sidemarker, Park, Turn Signal Bulb Replacement (TT8) (Service and Repair)Headlamp Assembly or Headlamp Bulb and/or Cornering, Sidemarker, Park, Turn Signal Bulb Replacement (Minus TT6/TT7/TT8/T84/T85) (Service and Repair)
* Control Module References (Programming and Relearning) for headlamp control module replacement, setup, and programming