GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the BCM diagnostic system check performed?

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Go to Step 2

Go to Diagnostic System Check - Body Control System

2

  1. Close all vehicle doors.
  2. Ensure the IP dimmer switch is set to the OFF position.
  3. Turn on the interior lamps override switch (enabling the interior lights).
  4. Turn the ignition switch to the RUN position.
  5. Open, then close all vehicle doors, one door at a time.

Did the courtesy lights turn on with a door open, and turn off with all the doors closed?

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Go to Step 3

Go to Step 5

3

  1. Ensure all vehicle doors are closed.
  2. Turn the ignition switch from the RUN position to the LOCK position.
  3. While observing the courtesy lights, remove key from the ignition key cylinder.

Did the courtesy lights turn on when removing the key from the ignition key cylinder?

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Go to Step 4

Go to Step 6

4

  1. Insert key in the ignition key lock cylinder.
  2. Leave the ignition switch in the LOCK position.
  3. Open the driver's door.
  4. While observing the door locks, press lock on door lock switch momentarily.
  5. Close the driver's door.
  6. Open the LH sliding door (if equipped).
  7. While seated in the driver's seat press lock on door lock switch momentarily; observe the door locks.
  8. Open the RF door and within 3 seconds, press lock on door lock switch momentarily while observing the door locks.
  9. Close the RF door.
  10. Open the RH sliding door.
  11. Press lock on door lock switch momentarily; observe the door locks.

Doors do not lock when pressing lock on either door lock switch with the key in the ignition key lock cylinder and a door open.

Do the door locks operated as described above?

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Go to Step 7

Go to Step 8

5

The lockout prevention feature is malfunctioning due to a malfunction between the BCM and the driver's door lock ajar switch. Refer to Interior Lamps System Check for diagnosis and repair of the interior lights' door lock ajar input.

Is the action complete?

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Go to Step 9

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6

The lockout prevention feature is inoperative due to a malfunction between the BCM and the ignition key alarm switch. Refer to Diagnostic System Check - Audible Warnings for diagnosis and repair of the key in ignition reminder chime and the ignition key alarm switch.

Is the action complete?

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Go to Step 9

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7

The lockout prevention feature is working as designed. Refer to Automatic Door Lock Circuit Description for more information.

Is the action complete?

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Go to Step 9

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8

  1. Inspect the BCM connectors for poor terminal contact.
  2. If BCM connectors are OK, replace the BCM. Refer to Body Control Module Replacement in Body Control Systems.

Is the repair complete?

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Go to Step 9

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9

  1. Turn the ignition switch to the LOCK position.
  2. Reinstall connectors/components removed.
  3. Turn the ignition switch to the RUN position for 6 seconds.
  4. Turn the ignition switch to the LOCK position.
  5. Remove the BCM PRGRM fuse.
  6. Turn the ignition switch to the ACC position. (The BCM sounds the chime a number of times equivalent to the BCM type installed on the vehicle).
  7. Within one second, turn the ignition switch from the ACC position, to the LOCK position, then back to the ACC position. (The BCM sounds any DTCs stored).

Are there any BCM DTCs present?

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Go to Diagnostic System Check - Body Control System

Go to Automatic Door Locks System Check