Cadillac 2011 DTS Owner's Manual page 182

The exterior lamps control has four positions:
Turns off the exterior lamps except for Daytime
Running Lamps (DRL).
Automatically turns on the
headlamps at normal brightness, together with the
following:
Parking Lamps
Instrument Panel Lights
®
IntelliBeam
Turns on the parking lamps
together with the following:
Instrument Panel Lights
License Plate Lamps
Taillamps
Side Marker Lamps
The parking brake indicator light comes on and stays on
while the parking lamps are on with the engine off and
the ignition in ACC/ACCESSORY or ON/RUN.
Turns on the headlamps together with
the previously listed lamps. A warning chime sounds if
the driver's door is opened while the ignition switch is
off and the headlamps are on.
Press the exterior lamps control to
turn on the fog lamps. See Fog Lamps on page 4 28.
4-24
For vehicles with this feature, be sure to read this entire
section before using it.
IntelliBeam is an enhancement to the vehicle's
headlamp system. Using a digital light sensor on
the rearview mirror, this system turns the vehicle's
high-beam headlamps on and off according to
surrounding traffic conditions.
The IntelliBeam system turns the high-beam headlamps
on when it is dark enough, there is no other traffic
present, and the IntelliBeam system is enabled.
Press and release the IntelliBeam button on the inside
rear view mirror. The IntelliBeam indicator on the mirror
turns on to indicate the system is on. Once the system
has been turned on, it remains on each time the vehicle
is started, but the IntelliBeam system must be enabled.
To enable the IntelliBeam system, turn the exterior lamp
control to AUTO, with the turn signal/multifunction lever
in its neutral position. The High-Beam On Light appears
on the instrument panel cluster when the high-beams
are on. See Highbeam On Light on page 4 56.