GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

DEFINITION: The courtesy lights do not turn on for 40 seconds when unlocking the doors using the door key cylinder.

1

Was the Interior Lights System Check performed?

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Go to Step 2

Go to Interior Lamps System Check

2

Was the BCM Diagnostic System Check performed?

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Go to Step 3

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

3

Check the service parts identification label for RPO UA6. Refer to RPO Code List in General Information.

Is the vehicle equipped with the content theft deterrent (RPO UA6)?

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Go to Step 4

Go to Step 14

4

  1. Open the driver's door.
  2. Manually lock the driver's door.
  3. Disconnect the body control module (BCM) connector C2.
  4. Insert the key in the driver's door cylinder lock.
  5. Usinga test light probe B+ and the BCM harness connector C2 terminal C5.
  6. While observing the test light, rotate the key in order to unlock the door. Hold the key in the unlock position for one second.

Does the test light illuminate upon unlocking the door using the key?

--

Go to Step 7

Go to Step 5

5

  1. Disconnect the driver's door left side key cylinder lock switch electrical connector.
  2. Using a test light probe between B+ and the key cylinder lock switch harness connector terminal A.

Does the test light illuminate?

--

Go to Step 6

Go to Step 9

6

Using a DMM measure the resistance between the key cylinder lock switch harness connector terminal B and the BCM harness connector C2 terminal C5.

Is the resistance within the specified range?

Less than 2 ohms

Go to Step 11

Go to Step 12

7

  1. Remove the key from the left front door.
  2. Open the right front door.
  3. Manually lock the right front door.
  4. Insert the key in the right front door cylinder lock.
  5. Using a test light probe B+ and the BCM harness connector C2 terminal C5.
  6. While observing the test light, rotate the key in order to unlock the door.

Does the test light illuminate upon unlocking the door using the key?

--

Go to Step 13

Go to Step 8

8

  1. Disconnect the passenger's door right side key cylinder lock switch electrical connector.
  2. Using a test light probe between B+ and the key cylinder lock switch harness connector terminal A.

Does the test light illuminate?

--

Go to Step 6

Go to Step 10

9

Repair the poor connection or an open in circuit 750.

Is the repair complete?

--

Go to Step 14

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10

Repair the poor connection or an open in circuit 350.

Is the repair complete?

--

Go to Step 14

--

11

Replace the key cylinder lock switch.

Is the repair complete?

--

Go to Step 14

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12

Repair the poor connection or an open in circuit 781.

Is the repair complete?

--

Go to Step 14

--

13

    • Inspect the BCM connector C2 terminal C5 for a poor terminal contact.
    • If the BCM connector C2 terminal C5 is OK, then replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Is the repair complete?

--

Go to Step 14

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14

  1. Turn the ignition switch to the OFF position.
  2. Reinstall the connectors and components removed.
  3. Turn the ignition switch to the RUN position for 6 seconds.
  4. Turn the ignition switch to the OFF position.
  5. Remove the MALL PGM 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 OFF position, then back to the ACC position. (The BCM sounds any DTCs stored.)

Are there any BCM DTCs present?

--

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

Go to Interior Lamps System Check