GM Service Manual Online
For 1990-2009 cars only

Twilight Sentinel® can turn your lamps on and off for you.


Object Number: 1455727  Size: B3

A light sensor on top of the instrument panel makes the Twilight Sentinel® work, so be sure it is not covered.

With Twilight Sentinel® you will see the following happen:

    • When it is dark enough outside, the front turn signal lamps (DRL) will go off, and the headlamps and parking lamps will come on. The other lamps that come on with headlamps will also come on.
    • When it is bright enough outside, the headlamps will go off, and the front turn signal lamps (DRL) will come on, as long as the exterior lamp switch is in the off position.

If you start your vehicle in a dark garage, the automatic headlamp system will come on immediately. Once you leave the garage, it will take approximately one minute for the automatic headlamp system to change to DRL if it is light outside. During that delay, your instrument panel cluster may not be as bright as usual. Make sure your instrument panel brightness control is in full bright position. See Instrument Panel Brightness for more information.

You can idle the vehicle with the lamps off, even when it is dark outside. First set the parking brake while the ignition is in OFF/ACC. Then start the vehicle. The lamps will stay off until you release the parking brake.

Twilight Sentinel® also provides exterior illumination as you leave the vehicle. If Twilight Sentinel® has turned on the lamps when you turn off the ignition, your lamps will remain on until:

    • The exterior lamp switch is moved from off to the parking lamp position, or
    • a delay time that you select has elapsed.

See Vehicle Personalization to select the delay time that you want. You can also select no delay time.

If you turn off the ignition with the exterior lamp switch in the parking lamp or headlamp position, the Twilight Sentinel® delay will not occur. The lamps will turn off as soon as the switch is turned off.

As with any vehicle, you should turn on the regular headlamp system when you need it.