B3868

DTC B3868 or B3869

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 B3868 00
- Left Side Repeater Circuit Malfunction

DTC B3869 00
- Right Side Repeater Circuit Malfunction




Diagnostic Fault Information






Circuit/System Description

The turn signal switch is integrated into the steering column module. When the turn signal switch is activated, the steering column module interprets the position of the switch and sends a serial data message to the underhood electrical center (UEC) and the rear electrical center (REC) requesting either the right or left turn signals be activated. The UEC and REC respond by applying a pulsating voltage to the appropriate turn signal control circuits to illuminate the front and rear turn signal lamps. The steering column module also sends a serial data message to the instrument panel cluster (IPC) requesting the appropriate turn signal indicator be illuminated.


Conditions for Running the DTC

* Battery voltage must be between 9-16 volts.
* Left or right turn signals ON.



Conditions for Setting the DTC

B3868 00

The DTC will set when the UEC detects a short to ground or an open/high resistance in the left front repeater control circuit.

B3869 00

The DTC will set when the UEC detects a short to ground or an open/high resistance in the right front repeater control circuit.


Actions Taken When the DTC Sets

B3868 00

The UEC will disable the left front repeater control circuit.

B3869 00

The UEC will disable the right front repeater control circuit.


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

Exterior Lights Schematics (Exterior Lights 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 repeater lamp.
2. Ignition OFF, exterior lamps OFF, test for less than 5.0 ohms between the ground circuit terminal 2 and ground.

• If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the control circuit terminal 1 and ground.
4. Command the Side Repeater 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 UEC.
• 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 UEC.

5. If all circuits test normal, replace the inoperative repeater lamp.



Repair Instructions

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

* Repeater Lamp Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for UEC replacement, setup, and programming