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B0685



DTC B0685

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview
* Review Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B0685 01
- Security System Indicator Circuit Short to Battery

DTC B0685 06
- Security System Indicator Circuit Short to Ground or Open

Diagnostic Fault Information






Circuit/System Description

The security indicator is controlled by the body control module (BCM) based on commands from the immobilizer system or the content theft deterrent (CTD) system. With the ignition OFF, the security indicator is commanded by the CTD system. With the ignition ON, the security indicator is commanded by the immobilizer system.

The security indicator is located in the instrument panel cluster (IPC) and is supplied B+ at all times. When the immobilizer or CTD system requests the indicator be commanded ON, the BCM grounds the security indicator control circuit, illuminating the indicator.

Conditions for Running the DTC

Battery voltage is 9-16 volts.

Conditions for Setting the DTC

B0685 01

The BCM detects a short to ground on the security indicator control circuit.

B0685 06

The BCM detects a short to voltage or an open on the security indicator control circuit.

Action Taken When the DTC Sets

Security indicator output is disabled

Conditions for Clearing the DTC

* A current DTC is cleared when the conditions for setting the DTC are no longer present.
* A history DTC will clear after 40 malfunction free ignition cycles.

Circuit/System Verification

Ignition ON, command the security indicator ON and OFF with a scan tool. The security indicator should turn ON and OFF when changing between the commanded states.

Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the IPC.
2. Connect a test lamp between the control circuit terminal 10 and B+.
3. Command the security indicator 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 ground. If the circuit tests normal, replace the BCM.
If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

4. If all circuits test normal, replace the IPC.

Repair Instructions

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