B356A

DTC B356A

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* ReviewStrategy 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 Descriptor
DTC B356A 02
- Vehicle Direction Alert Alarm Warning Switch Circuit Short to Ground


Diagnostic Fault Information





Circuit/System Description

The lane departure warning (LDW) system consists of a vehicle direction alert alarm warning (VDAAW) module mounted on the windshield. The VDAAW is enabled and disabled through a switch located in the headlamp switch assembly. When enabled, the VDAAW will illuminate the indicator located in the switch. A camera located in the LDW module is used to locate lane markings in the road. When the system is working and can detect the lane markings, the VDAAW will illuminate the lane departure warning indicator in the instrument panel cluster (IPC). The IPC indicator will illuminate green when the system is operating properly and flash amber when the vehicle crosses a lane marking without the turn signal being used. An audible warning will also sound three times when the IPC indicator is flashing. The VDAAW system communicates with the IPC via serial data.

Conditions for Running the DTC

The system voltage is between 9-16 volts.

Conditions for Setting the DTC

The VDAAW module detects a short to ground on the switch signal circuit.

Action Taken When the DTC Sets

* The VDAAW module disables the system.
* The SERVICE LANE DEPARTURE SYSTEM message is displayed on the DIC.

Conditions for Clearing the DTC

* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 100 consecutive malfunction-free ignition cycles have occurred.

Reference Information
Schematic Reference

Object Detection Schematics ([1][2]Collision Avoidance and Parking Assist Systems)
Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Object Detection Description and Operation (Rear Parking Assist) (Object Detection Description and Operation (Rear Parking Assist))Object Detection Description and Operation (VDAAW) (Object Detection Description and Operation (VDAAW))Object Detection Description and Operation (SOD) (Object Detection Description and Operation (SOD))
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 Verification

Ignition ON, observe the scan tool Mode Switch parameter while pressing the lane departure warning switch. The parameter should change between Active and Inactive.

Circuit/System Testing

Important: Before disconnecting the harness connector at the VDAAW module, ensure that the ignition has been OFF for at least 120 seconds. Failure to do so may result in component damage.


1. Ignition OFF for 120 seconds, disconnect the harness connector at the headlamp switch.
2. Ignition ON, verify the scan tool Mode Switch parameter is Inactive.

• If not the specified value, test the signal circuit terminal 9 for a short to ground. If the circuit tests normal, replace the VDAAW module.

3. Install 3A fused jumper wire between the signal circuit terminal 9 and ground. Verify the scan tool Mode Switch parameter is Active.

• If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the VDAAW module.

4. If all circuits test normal, test or replace the headlamp switch.

Component Testing

1. Ignition OFF, disconnect the harness connector at the headlamp switch.
2. Test for infinite resistance between the signal circuit terminal 9 and the ground circuit terminal 8 with the switch in the Open position.

• If the specified value, replace the headlamp switch.

3. Test for less than 2 ohms between the signal circuit terminal 9 and the ground circuit terminal 8 with the switch in the Closed position.

• If greater than the specified range, replace the headlamp switch.


Repair Instructions

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

* Headlamp Switch Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for VDAAW module replacement, setup and programming