GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Impala 🢒 DTC 🢒 DTC B3064 or B3069

Circuit Description

The door lock cylinder switches provide a direct ground input to the body control module (BCM) when one of the switches is activated. This input allows the BCM to detect when the door lock cylinder switches are turned to the unlock position. When the BCM detects that a door lock cylinder switch is in the unlock position for greater than one second, it will perform an output command to unlock all the doors. This input is also needed for the optional content theft deterrent system when the keyless entry feature does not unlock the doors.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B3069 Right Front/Left Front Door Key Unlock Switch Circuit Low

Conditions for Setting the DTC

The BCM detects a short to ground in the driver door key switch signal circuit for greater than 60 seconds.

Action Taken When the DTC Sets
    • The BCM stores DTC B3069 in memory.
    • The BCM disables all output operations associated with the input.

Conditions for Clearing the DTC
    • A current DTC B3069 is cleared when the BCM no longer detects a short to ground in the driver door key switch signal circuit for greater than 60 seconds.
    • A history DTC B3069 is cleared after 100 consecutive ignition cycles with the condition for setting the DTC no longer present.
    • The DTC is cleared using a scan tool.

Diagnostic Aids
    • If DTC B3069 is a history DTC, the fault may be intermittent. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
    • The following conditions may cause an intermittent malfunction to occur:
       - An intermittent short to ground in the driver door key switch signal circuit
       - A door lock cylinder switch intermittently shorted to ground
       - A door lock cylinder switch that was held in the Unlock position for greater than 60 seconds
       - The BCM intermittently shorted to ground internally

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests to determine if the short to ground in the driver door key switch signal circuit is present.

    2.

  2. This step tests to determine if the short to ground in the driver door key switch signal circuit is intermittent.

    3.

  3. This step tests to determine if the driver door lock cylinder switch is shorted to ground.

    4.

  4. This step tests to determine if the front passenger door lock cylinder switch is shorted to ground.

Step

Action

Yes

No

Schematic Reference: Door Lock/Indicator Schematics

Connector End View Reference: Power Door Systems Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

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 in the body control module (BCM) data list.

Does the scan tool display Off?

Go to Step 3

Go to Step 4

3

  1. Activate a door lock cylinder switch.
  2. With a scan tool, observe the key cylinder unlock parameter in the BCM data list.

Does the key cylinder unlock parameter change state?

Go to Diagnostic Aids

Go to Step 7

4

  1. Turn OFF the ignition.
  2. Disconnect the driver door lock cylinder switch.
  3. Turn ON the ignition, with the engine OFF.
  4. With a scan tool, observe the key cylinder unlock parameter in the BCM data list.

Does the scan tool display Off?

Go to Step 8

Go to Step 5

5

  1. Turn OFF the ignition.
  2. Connect the driver door lock cylinder switch.
  3. Disconnect the front passenger door lock cylinder switch.
  4. Turn ON the ignition, with the engine OFF.
  5. With a scan tool, observe the key cylinder unlock parameter in the BCM data list.

Does the scan tool display Off?

Go to Step 8

Go to Step 6

6

Test the door key switch signal circuit 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 11

Go to Step 7

7

Inspect for poor connections at the harness connector of the BCM. 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 11

Go to Step 9

8

Inspect for poor connections at the harness connector of the inoperative door lock cylinder switch. 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 11

Go to Step 10

9

Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 11

--

10

Replace the inoperative door lock cylinder switch. Refer to Door Lock Cylinder Replacement .

Did you complete the replacement?

Go to Step 11

--

11
  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