2004 CHEVROLET CLASSIC sensor

Exterior Lamps
Headlamps
See “Headlamps” underTurn Signal/Multifunction Lever
on page 3-6.
Daytime Running Lamps (DRL)
Daytime Running Lamps (DRL) can make it easier for
others to see the front of your vehicle during the
day. DRL can be helpful in many different driving
conditions, but they can be especially helpful in the short
periods after dawn and before sunset.
The DRL system will make your low-beam headlamps
come on at a reduced brightness when the following
conditions are met:
•The ignition is on,
•the exterior lamp control is turned to AUTO or you
have turned on your parking lamps,
•the light sensor detects daytime light,
•the parking brake is released, and
•the shift lever is not in PARK (P).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.
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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” underInterior 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.Headlamps Off in Park (P)
This feature works when the ignition is on and it is dark
outside. To turn the headlamps off when it is dark outside,
turn the exterior lamp control to the parking lamp position.
In this position, the parking lamps, sidemarker lamps,
taillamps, license plate lamps and instrument panel lights
will be on, but the headlamps will be off.
To turn on the headlamps along with the other lamps
when it is dark outside, turn the exterior lamp control to
the AUTO or headlamp position.
Delayed Headlamps
The delayed headlamps feature will continue to
illuminate the headlamps for 20 seconds after the key is
turned to OFF at night. Then the headlamps will
automatically turn off.
To override the 20 second delayed headlamp feature
while it is active turn the switch at the end of the
turn signal/multifunction lever up one position and then
back to AUTO.
3-14

Air Bag Readiness Light
There is an air bag readiness light on the instrument
panel, which shows the air bag symbol. The system
checks the air bag’s electrical system for malfunctions.
The light tells you if there is an electrical problem.
The system check includes the air bag sensor, the air
bag modules, the wiring and the crash sensing and
diagnostic module. For more information on the air bag
system, seeSupplemental Restraint System (SRS)
on page 1-56.
This light will come on
when you start your
vehicle, and it will flash for
a few seconds. Then the
light should go out. This
means the system is ready.
If the air bag readiness light stays on after you start the
vehicle or comes on when you are driving, your air
bag system may not work properly. Have your vehicle
serviced right away.{CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inate in a crash, or they
could even inate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a few
seconds when you turn the ignition key to ON. If the
light doesn’t come on then, have it fixed so it will
be ready to warn you if there is a problem.
3-26

Relays Usage
17 Not Used
18 Fuel Pump
19 Automatic Headlamp System
20 Automatic Headlamp System
21 Horn
22 Daytime Running Lamps (DRL)
Fuses Usage
23–32 Spare Fuse Holder
33 Rear Defogger
34Accessory Power Outlets, Cigar
Lighter
35 Not Used
36 Not Used
37Air Conditioning Compressor, Body
Function Control Module
38 Automatic Transaxle
39Powertrain Control Module (PCM),
Ignition
40 Anti-Lock Brakes (ABS)
Fuses Usage
41 Ignition System
42Back-Up Lamps, Shift Lock Control
System
43 Horn
44 PCM
45 Parking Lamps
46 Climate Control System
47Canister Purge Valve, PCM,
Exhaust Gas Recirculation, Heated
Oxygen Sensor
48 Fuel Pump Injectors
49 Not Used
50 Right Headlamp
51 Left Headlamp
52 Cooling Fan
53 HVAC Blower (Climate Control)
54 Not Used
55 Not Used
56 Fuse Puller
57 Not Used
5-94