Chevrolet Malibu 2003 Manual page 107

When the DRL system is on, the taillamps, sidemarker
lamps, parking lamps and instrument panel lights
will not be illuminated unless you have turned the
exterior lamps control to the parking lamp or headlamp
position.
The DRL system will remain off any time your vehicle is
in PARK (P) or the parking brake is engaged and the
vehicle speed is less than 8 mph (13 km/h), for
United States vehicles only.
As with any vehicle, you should turn on the regular
headlamp system when you need it.
Automatic Headlamp System
When it is dark enough outside, your Automatic
Headlamp System will turn on your headlamps at the
normal brightness along with other lamps such as
the taillamps, sidemarker, parking lamps and the
instrument panel lights. The radio lights will also be dim.
Your vehicle is equipped with a light sensor on the
top of the instrument panel under the defroster grill,
so be sure it is not covered which will cause the system
to be on whenever the ignition is on.
The system may also be on when driving through a
parking garage, heavy overcast weather or a tunnel.
This is normal.
There is a delay in the transition between the daytime
and nighttime operation of the DRL and the Automatic
Headlamp System so that driving under bridges or bright
overhead street lights does not affect the system. The
DRL and Automatic Headlamp System will only be
affected when the light sensor sees a change in lighting
lasting longer than this delay.
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 the full bright position. See "Instrument
Panel Brightness Control" under Interior Lamps
on page 3-15 .
To idle your vehicle with the system off, set the park
brake while the ignition is off. Then start the vehicle.
The system will stay off until you release the park brake.
As with any vehicle, you should turn on the regular
headlamps when you need them.
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