B3445
DTC B3445
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category
DTC Descriptor
DTC B3445 00
-
Stop Lamp Circuit
Diagnostic Fault Information
Circuit/System Description
The brake pedal position sensor is used to sense the action of the driver application of the brake pedal. The brake pedal position sensor provides an analog voltage signal that will increase as the brake pedal is applied. The body control module (BCM) provides a low reference signal and a 5-volt reference voltage to the brake pedal position sensor. When the variable signal reaches a voltage threshold indicating the brakes have been applied, the BCM will apply battery voltage to the stop lamp control circuit illuminating the left and right stop lamps and the center high mounted stop lamp (CHMSL). The BCM also applies battery voltage to the engine control module (ECM) via the brake applied signal circuit.
Conditions for Running the DTC
* Battery voltage must be between 9-16 volts.
* Brakes APPLIED.
Conditions for Setting the DTC
* The BCM detects a short to ground or an open/high resistance in the F10DA fuse B+ circuit.
* The BCM detects a short to ground in the stop lamp control circuit when the stop lamps are being commanded ON.
Actions Taken When the DTC Sets
The BCM will not illuminate the stop lamps.
Conditions for Clearing the DTC
* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 100 malfunction-free ignition cycles have occurred.
Reference Information
Schematic Reference
* Exterior Lights Schematics Exterior Lights Schematics
* Body Control System Schematics [1][2]Body Control Systems
Connector End View Reference
Component Connector End Views Fuel Pump and Level Sensor Assembly
Description and Operation
Exterior Lighting Systems Description and Operation Exterior Lighting Systems
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
Scan Tool Reference
Control Module References Control Module References for scan tool information
Circuit/System Testing
1. Ignition OFF, disconnect the X4 harness connector at the K9 body control module.
2. Verify that a test lamp illuminates between the B+ circuit terminal 4 and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
3. Connect the X4 harness connector at the K9 body control module.
4. Disconnect the harness connectors at the following components:
* E6 center high mounted stop lamp
* E42L tail lamp assembly - left
* E42R tail lamp assembly - right
5. Connect a test lamp between the control circuit terminal 4 at the E42R tail lamp assembly - right and ground.
6. Ignition ON, command the Brake Light Test ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
• If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K9 body control module.
• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 body control module.
7. Reconnect each component one at a time and verify the DTC does not reset as current.
• If the DTC resets as current, test or replace the component responsible for setting the DTC.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
* High Mount Stop Lamp Replacement Service and Repair
* Stop and Tail Lamp Bulb Replacement Stop and Tail Lamp Bulb Replacement
* Control Module References Control Module References for BCM replacement, setup, and programming