2010 GMC Acadia Owner's Manual - Page 186

6-6 Lighting When the ignition is on, illuminated entry is inactive, which means the courtesy lamps will not come on unless a door is opened. Lighting Features Entry Lighting For vehicles with courtesy lamps, they come on and stay on for a set time whenever the unlock symbol is pressed on the Remote Keyless Entry (RKE) transmitter, if the vehicle has one. If a door is opened, the lamps stay on while it is open and then turn off automatically about 20 seconds after the door is closed. If the unlock symbol is pressed and no door is opened, the lamps turn off after about 20 seconds. Entry lighting includes a feature called theater dimming. With theater dimming, the lamps do not turn off at the end of the delay time. Instead, they slowly dim and then go out. The delay time is canceled if the ignition key is turned to ON/RUN or the power door lock switch is pressed. The lamps will dim right away. Delayed Exit Lighting Delayed exit lighting illuminates the interior for a period of time after the key is removed from the ignition. The ignition must be off for delayed exit lighting to work. When the key is removed, interior illumination activates and remains on until one of the following occurs: . . Delayed Entry Lighting Delayed entry lighting illuminates the interior for a period of time after all the doors have been closed. The ignition must be off for delayed entry lighting to work. Immediately after all the doors have been closed, the delayed entry lighting feature continues to work until one of the following occurs: ... The ignition is in ON/RUN. The power door locks are activated. An illumination period of 20 seconds has elapsed. . The ignition is in ON/RUN. The doors are locked. An illumination period of about 25 seconds has elapsed. If during the illumination period a door is opened, the timed illumination period will be canceled and the interior lamps will remain on because a door is open. If during the illumination period a door is opened, the timed illumination period is canceled and the interior lamps remain on.