GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The body control module (BCM) receives a vehicle security powertrain status message from the powertrain control module (PCM) through the Class 2 serial data link when turning the ignition switch ON.

Conditions for Setting the DTC

The BCM sets DTC B3094 when the BCM does not receive a vehicle security powertrain status message from the PCM within one minute of turning the ignition switch ON.

Action Taken When the DTC Sets

    • The BCM stores DTC B3094 in memory.
    • The BCM sends a message to the instrument cluster to turn on the SECURITY indicator.

Conditions for Clearing the DTC

    • B3094 DTC status changes from current to history when the BCM receives the vehicle security powertrain status message from the PCM.
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the fault is no longer present.

Diagnostic Aids

    • The following conditions may cause an intermittent malfunction to occur:
       - An intermittent open in the class 2 serial data link between the BCM and the PCM
       - Poor connections at the BCM, PCM, or the vehicle star connector
    • If DTC B3094 is set as a current DTC, a serial data communication malfunction exists. Refer to Symptoms - Data Link Communications .
    • DTC P1626 will set in the Powertrain Control Module (PCM) when the ignition switch is on with the BCM disconnected.

Step

Action

Yes

No

Schematic Reference: Theft Deterrent System Schematics

1

Did you perform the Theft Deterrent Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Theft Deterrent

2

  1. Install a scan tool.
  2. Turn ON the ignition with the engine OFF.
  3. Select the BCM Display DTCs function on the scan tool.

Does the scan tool display B3094 as a current DTC?

Go to Diagnostic Aids

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems