GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

DEFINITION: This procedure works only in locking control modes 2, 3 or 4.

1

Was the Body Control Module Diagnostic System Check performed?

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Go to Step 2

Go to Diagnostic System Check - Body Control System in Body Control System

2

Set the automatic door lock operation to mode 3. Refer to Automatic Door Lock Feature Customization .

Is the action complete?

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Go to Step 3

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3

  1. Turn the ignition switch to the RUN position.
  2. Step firmly on the brake pedal.
  3. Shift transaxle into the REVERSE position.
  4. With help of an assistant, observe the backup lights.
  5. Shift the transaxle into the PARK position.

Did the backup lights turn on when the transaxle was in the REVERSE position?

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Go to Step 4

Go to Step 6

4

  1. Verify that transaxle is in the PARK position.
  2. Use a test lamp in order to backprobe between the BCM connector C2 terminal D6 and ground.

Does the test lamp light?

--

Go to Step 7

Go to Step 5

5

  1. Turn the ignition switch to the LOCK position.
  2. Disconnect the transaxle range switch electrical connector C1.
  3. Disconnect the BCM connector C2.
  4. Using a J 39200 DMM, measure the resistance between the transaxle range switch harness connector C1 terminal C and the BCM harness connector C2 terminal D6.

Is the resistance less than the specified range?

2ohms

Go to Step 8

Go to Step 9

6

The automatic door lock feature in inoperative due to a malfunction in the backup lights B+ feed circuit. For diagnosis and repair, refer to Backup Lamp System Check in Lighting Systems.

Is the action complete?

--

Go to Step 10

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7

  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?

--

Go to Step 10

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8

Refer to Park/Neutral Position Switch Adjustment or to Park/Neutral Position Switch Replacement in Automatic Transaxle.

Is the repair complete?

Go to Step 10

9

Repair the poor connection or open in CKT 275.

Is the repair complete?

--

Go to Step 10

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10

  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 in Body Control System

Go to Automatic Door Locks System Check