GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Century (China) (CNG) 🢒 Body and Accessories 🢒 Body Control System 🢒 Interior Lamps System Check

Step

Action

Normal Result(s)

Abnormal Result(s)*

1
  1. Turn off the instrument panel (IP) dimmer switch.
  2. Turn off the left hand (LH) and the right hand (RH) roof rail courtesy/reading lamps.
  3. Turn off the inside rearview mirror reading lamps.
  4. Turn the ignition switch to the RUN position.
  5. Lower the driver door window in order to prevent a lockout.
  6. While observing the courtesy lights, open and close all of the vehicle doors, one door at a time.
    • The courtesy lights turn on when any door is open.
    • The courtesy lights turn off when all doors close.
    •  Dome Lamps Inoperative

2
  1. Close all of the vehicle doors.
  2. While observing the lights, turn the IP dimmer switch to the DOME position.
  3. Turn the IP dimmer switch OFF.
    • The courtesy lights turn on when the IP dimmer switch is in the DOME position.
    • The courtesy lights turn off when the IP dimmer switch is OFF.

Courtesy Lamps Inoperative with Instrument Panel Dimmer Switch

3
  1. Turn the ignition switch to the LOCK position.
  2. Open a vehicle door for at least 5 seconds. Close the door.
  3. Observe the courtesy lights.

Delayed illumination feature:

The courtesy lights turn on for 22.5-27.5 seconds then turn off after the last door closes.

Personalization Mode Inoperative

4
  1. Ensure that the ignition switch is in the LOCK position.
  2. Turn the IP dimmer switch to the DOME position for at least 20 minutes.
    • When any of the interior lights are left on for more the 18-22 minutes with the ignition switch in the LOCK or the OFF position, the interior lights turn off.
    • Important: On vehicles with less than 13.5-16.5 total accumulated miles, the interior lights turn off after 2.42-3.18 minute instead of 18-22 minutes.

Courtesy Lamps Always On

5
  1. Turn the ignition switch from the LOCK to the RUN position. Turn the ignition switch back to the LOCK position.
  2. Open a vehicle door for at least 5 seconds. Close all of the vehicle doors.
  3. While observing the courtesy lights, turn the ignition switch to the RUN position with in 25 seconds after you close the last door.
  4. Turn the ignition switch to the LOCK position.
  5. Open a vehicle door for at least 5 seconds. Close all of the vehicle doors.
  6. While observing the courtesy lights, press any power door lock switch to the LOCK position within 25 seconds after you close the last door.
    • The delayed illumination feature cancels (turning off the courtesy lights) when the ignition switch turns to the RUN position.
    • The delayed illumination feature cancels (turning off the courtesy lights) when pressing LOCK on a power door lock switch.

Personalization Mode Inoperative

6
  1. Close all of the vehicle doors.
  2. Turn the ignition switch from the LOCK position to the RUN position. Turn the ignition switch back to the LOCK position.
  3. While observing the courtesy lights, remove the key from the ignition switch.

Exit lighting feature: The courtesy lights turn on for 22.5-27.5 seconds upon removing the key from the ignition switch.

Personalization Mode Inoperative

7
  1. Ensure that you remove the key from the ignition switch.
  2. Close all of the vehicle doors.
  3. While observing the courtesy lights, press unlock on the keyless entry transmitter.
  4. Wait for 40 seconds.
  5. While observing the courtesy lights, press unlock on the keyless entry transmitter again.
  6. Within 40 seconds after pressing unlock, press lock on the keyless entry transmitter.
  1. The courtesy lights turn on for 36-44 seconds upon pressing unlock on the keyless entry transmitter.
  2. During the 36-44 seconds illumination period, the courtesy lights turn off when pressing lock on the keyless entry transmitter.

Courtesy Lamps Inoperative with Transmitter

8
  1. Close all of the vehicle doors.
  2. Ensure that the IP dimmer switch is off.
  3. Turn the ignition switch to the RUN position.
  4. Turn on, then off, the switches for the inside rearview mirror reading lamps.
    • The inside rearview mirror reading lamps turn on when the switches are on.
    • The inside rearview mirror reading lamps turn off when the switches are off.

9
  1. Close all of the vehicle doors.
  2. Ensure that the IP dimmer switch is off.
  3. Ensure that the ignition switch is in the RUN position.
  4. Turn on, then off, the switches for the LH and the RH roof rail courtesy/reading lamps.
    • The LH and the RH roof rail courtesy/reading lamps turn on when the switches are on.
    • The LH and the RH roof rail courtesy/reading lamps turn off when the switches are off.

10

Open, then close, the IP compartment while observing the IP compartment lamp.
    • The IP compartment lamp turns on when the IP compartment is open.
    • The IP compartment lamp turns off when the IP compartment closes.

11

Open, then close, the rear compartment lid while observing the rear compartment lamp.
    • The rear compartment lamp turns on when the rear compartment lid is open.
    • The rear compartment lamp turns off when the rear compartment lid closes.

* Refer to the appropriate symptom diagnostic table for the applicable abnormal result.