GM Service Manual Online
For 1990-2009 cars only

Refer to Door Lock/Indicator Schematics .

Circuit Description

The key cylinder switch provides a direct ground input into the body control module (BCM) when you activate the switch. This input allows the BCM to detect when the front door key cylinders are turned to the unlock position. This input is needed for the optional content theft deterrent system when the keyless entry feature does not unlock the doors.

Conditions for Setting the DTC

The BCM detects a short to ground in the key unlock input circuit for longer than 60 seconds.

Action Taken When the DTC Sets

    • The BCM stores DTC B3069 in memory.
    • The BCM will disable the input and all operations of the input until the fault goes away.

Conditions for Clearing the DTC

    • A current DTC B3069 will clear if the BCM no longer detects a short to ground in the key unlock input circuit for longer than 60 seconds.
    • A history DTC B3069 will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • A scan tool may be used to clear the DTC.

Diagnostic Aids

    • If the DTC B3069 is a history DTC, the fault may be intermittent. Refer to Intermittents and Poor Connections.
    • The following conditions may cause an intermittent malfunction to occur:
       - An intermittent short to ground in the key unlock input circuit
       - The key cylinder switch is intermittently shorted to ground internally
       - The BCM is intermittently shorted to ground internally

Test Description

  1. Determines whether the short to ground in the key cylinder unlock circuit is present or intermittent.

  1. Tests for door lock cylinder switches that are shorted to ground or contacts closed at all times.

  1. Tests for a short to ground in the key unlock control circuit.

Step

Action

Value(s)

Yes

No

1

Did you perform the Diagnostic System Check for the door system?

--

Go to Step 2

Go to Diagnostic System Check - Door Systems

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the key cylinder unlock parameter.

Does the scan tool indicate that the key cylinder unlock parameter is inactive?

--

Go to Diagnostic Aids

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect both door lock cylinder switches.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the key cylinder unlock parameter.

Does the scan tool indicate that the key cylinder unlock parameter is inactive?

--

Go to Step 6

Go to Step 4

4

Test the key unlock control circuit of the switches to the front door lock cylinder for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 8

Go to Step 5

5

Inspect for poor connections at the harness connector of the body control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 8

Go to Step 7

6

Replace the door lock cylinder switch that is shorted to ground. Refer to Door Lock Cylinder Replacement .

Did you complete the replacement?

--

Go to Step 8

--

7

  1. Replace the body control module. Refer to Body Control Module Replacement in Body Control System.
  2. Perform the set up procedure for the Body Control Module. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System.

Did you complete the replacement?

--

Go to Step 8

--

8

  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the conditions for running the DTC as specified in the supporting text.

Does the DTC reset?

--

Go to Step 2

System OK