2008 CHEVROLET SILVERADO sensor

2(Headlamps):Turn the control to this position to
turn on the headlamps together with the following:
Parking Lamps
Instrument Panel Lights
Taillamps
License Plate Lamps
When the headlamps are turned on while the vehicle is
on, the headlamps turn off automatically 10 minutes
after the ignition is turned off. When the headlamps are
turned on while the vehicle is off, the headlamps will
stay on for 10 minutes before automatically turning off to
prevent the battery from being drained. Turn the
headlamp control to off and then back to the headlamp
on position to make the headlamps stay on for an
additional 10 minutes.
Push the turn signal/multifunction lever toward the
instrument panel to change the headlamps from low
beam to high beam.
Headlamps on Reminder
A reminder chime will sound when the headlamps or
parking lamps are manually turned on and your ignition
is off and a door is open. To disable the chime, turn
the light off.
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. Fully functional daytime
running lamps are required on all vehicles rst sold
in Canada.
The DRL system will come on when the following
conditions are met:
The ignition is on.
The exterior lamps control is in AUTO.
The transmission is not in PARK (P).
The light sensor determines it is daytime.
When the DRL are on, only the DRL lamps will be on.
The taillamps, sidemarker, and other lamps will not
be on. The instrument panel will not be lit up either.
When it begins to get dark, the automatic headlamp
system will switch from DRL to the headlamps.
To turn off the DRL lamps, turn the exterior lamps
control to the OFF position and then release. For
vehicles rst sold in Canada, the transmission must be
in the PARK (P) position, before the DRL lamps can
be turned off.
3-18

Automatic Headlamp System
When it is dark enough outside, the automatic headlamp
system will turn on the headlamps at the normal
brightness, along with the taillamps, sidemarker, parking
lamps, and the instrument panel lights. The radio lights
will also be dim.
To turn off the automatic headlamp system, turn the
exterior lamps switch to the off position and then release
it. For vehicles rst sold in Canada, the transmission
must be in the PARK (P) position, before the automatic
headlamp system can be turned off.
The vehicle has a light sensor located on the top of the
instrument panel in the defroster grille that regulates
when the automatic headlamps turn on. Be sure it is not
covered, or the headlamps will come on whenever
the ignition is on.
The system may also turn on the headlamps 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 Daytime
Running Lamps (DRL) and the automatic headlamp
systems 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 detects a change in
lighting lasting longer than the delay.
If the vehicle is started in a dark garage, the automatic
headlamp system will come on immediately. Once the
vehicle leaves the garage, it takes approximately
one minute for the automatic headlamp system to
change to DRL if it is bright enough outside. During that
delay, the instrument panel cluster may not be as
bright as usual. Make sure the instrument panel
brightness control is in the full bright position.
SeeInstrument Panel Brightness on page 3-21.
To idle the vehicle with the automatic headlamp system
off, turn the control to the off position.
The headlamps will also stay on after you exit the
vehicle. This feature can be programmed using the
Driver Information Center (DIC). SeeDIC Vehicle
Customization (With DIC Buttons) on page 3-76.
The regular headlamp system can be turned on
when needed.
3-19

2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 74°F (23°C)
temperature setting and allow about 20 minutes
for the system to regulate. Use the driver’s or
passenger’s temperature buttons to adjust the
temperature setting as necessary. If you choose the
temperature setting of 60°F (15°C), the system
remains at the maximum cooling setting. If you
choose the temperature setting of 90°F (32°C),
the system remains at the maximum heat setting.
Choosing either maximum setting will not cause the
vehicle to heat or cool any faster.
Be careful not to cover the solar sensor located on
the top of the instrument panel near the windshield.
This sensor regulates air temperature based on
sun load. For more information on the solar sensor,
see “Sensors” later in this section.
To avoid blowing cold air in cold weather, the system
delays turning the fan on until warm air is available.
The length of delay depends on the engine coolant
temperature. Pressing the fan switch overrides this delay
and changes the fan to a selected speed.O(On/Off):Press this button to turn off the climate
control system. Outside air still enters the vehicle, and
is directed to the oor. This direction can be changed by
pressing the mode button. Recirculation can be
selected once you have selected vent or bi-level mode.
The temperature can also be adjusted using either
temperature button. If the air delivery mode or
temperature settings are adjusted with the system off,
the display illuminates briey to show the settings
and then returns to off. Press the on/off button or the up
down arrows on the fan switch, the defrost button,
AUTO button, or the air conditioning button to turn the
system on when it is off.
3-31

Sensors
The solar sensor, located
in the defrost grille, in the
middle of the instrument
panel, monitors the
solar radiation. Do not
cover the solar sensor or
the system will not
work properly.
The interior temperature
sensor, located in the
headliner, measures the
temperature of the air
inside the vehicle.
There is also an exterior temperature sensor located
behind the front grille. This sensor reads the outside
air temperature and helps maintain the temperature
inside the vehicle. Any cover on the front of the
vehicle could cause a false reading in the displayed
temperature on the rearview mirror.The climate control system uses the information from
these sensors to maintain your comfort setting by
adjusting the outlet temperature, fan speed, and the
air delivery mode. The system may also supply
cooler air to the side of the vehicle facing the sun.
The recirculation mode will also be used as needed to
maintain cool outlet temperatures.
Defogging and Defrosting
Fog on the inside of the windows is a result of high
humidity (moisture) condensing on the cool window
glass. This can be minimized if the climate control
system is used properly. There are two modes to clear
fog or frost from the windshield.
Use
HandGto select the defog or defrost modes.
-(Defog):Press this button to clear the windows of
fog or moisture and warm the passengers. This mode
directs air to the windshield, oor outlets, and side
window vents. When this mode is selected, the system
turns off recirculation and runs the air conditioning
compressor unless the outside temperature is close to
freezing. The recirculation mode cannot be selected
while in the defog mode. Do not drive the vehicle until all
the windows are clear.
3-34

Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol.
The system checks the airbag’s electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the airbag
sensor, the pretensioners, the airbag modules, the
wiring and the crash sensing and diagnostic module.
For more information on the airbag system, seeAirbag
System on page 1-69.
This light will come on
when you start your
vehicle, and it will ash for
a few seconds. The light
should go out and the
system is ready.
If the airbag readiness light stays on after you start the
vehicle or comes on when you are driving, your
airbag system may not work properly. Have your vehicle
serviced right away.{CAUTION:
If the airbag readiness light stays on after you
start your vehicle, it means the airbag system
may not be working properly. The airbags 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.
The airbag readiness light should ash for a few seconds
when you start the engine. If the light does not come on
then, have it xed immediately. If there is a problem with
the airbag system, an airbag Driver Information Center
(DIC) message may also come on. SeeDIC Warnings
and Messages on page 3-66for more information.
3-40

You should change the oil as soon as you can.
SeeEngine Oil (Gasoline Engine) on page 5-15.
In addition to the engine oil life system monitoring
the oil life, additional maintenance is recommended
in the Maintenance Schedule in this manual.
SeeScheduled Maintenance (Gasoline Engine) on
page 6-4for more information.
Remember, you must reset the OIL LIFE display
yourself after each oil change. It will not reset itself.
Also, be careful not to reset the OIL LIFE display
accidentally at any time other than when the oil has just
been changed. It cannot be reset accurately until the
next oil change. To reset the engine oil life system,
seeEngine Oil Life System on page 5-18.
Relearn Tire Positions
Your vehicle may have this display. To access this
display, the vehicle must be in PARK (P). If your vehicle
has the Tire Pressure Monitor System (TPMS), after
rotating the tires or after replacing a tire or sensor,
the system must re-learn the tire positions. To re-learn
the tire positions, seeTire Pressure Monitor System
on page 5-78. SeeTire Inspection and Rotation
on page 5-83andDIC Warnings and Messages on
page 3-66for more information.
Relearn Remote Key
To access this display, the vehicle must be in PARK (P).
This display allows you to match Remote Keyless
Entry (RKE) transmitters to your vehicle. To match an
RKE transmitter to your vehicle:
1. Press the trip odometer reset stem until RELEARN
REMOTE KEY displays.
2. Press and hold the trip odometer reset stem for
three seconds.
The message REMOTE KEY LEARNING ACTIVE
will display.
3. Press and hold the lock and unlock buttons on
the rst transmitter at the same time for about
15 seconds.
On vehicles with memory recall seats, the rst
transmitter learned will match driver 1 and
the second will match driver 2.
A chime will sound indicating that the transmitter
is matched.
4. To match additional transmitters at this time,
repeat Step 3.
Each vehicle can have a maximum of
eight transmitters matched to it.
5. To exit the programming mode, you must cycle
the key to LOCK/OFF.
3-65

TIGHTEN GAS CAP
This message may display along with the check engine
light on the instrument panel cluster if the vehicle’s
fuel cap is not tightened properly. SeeMalfunction
Indicator Lamp on page 3-49. Reinstall the fuel cap fully.
SeeFilling the Tank on page 5-10. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap allows
fuel to evaporate into the atmosphere. A few driving trips
with the cap properly installed should turn this light
and message off.
TIRE LEARNING ACTIVE
If your vehicle has the Tire Pressure Monitor System
(TPMS), this message displays when the system
is re-learning the tire positions on your vehicle.
See “DIC Operation and Displays (Without DIC Buttons)”
earlier in this section for more information. The tire
positions must be re-learned after rotating the tires or
after replacing a tire or sensor. SeeTire Inspection and
Rotation on page 5-83,Tire Pressure Monitor System
on page 5-78, andInflation - Tire Pressure on page 5-76
for more information.
TRACTION CONTROL OFF
If your vehicle has StabiliTrak®, this message displays
when the Traction Control System (TCS) is turned
off. Adjust your driving accordingly. SeeStabiliTrak
®
System on page 4-6for more information.
TRAILER CONNECTED
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, this message displays briey when
a trailer with electric brakes is rst connected to
the vehicle.
This message clears itself after several seconds.
This message also clears if you acknowledge it.
After this message clears, the TRAILER GAIN/OUTPUT
display appears in the DIC.
See “TRAILER GAIN/OUTPUT” underDIC Operation
and Displays (With DIC Buttons) on page 3-57or
DIC Operation and Displays (Without DIC Buttons)
on page 3-63and “Integrated Trailer Brake Control
System” underTowing a Trailer on page 4-55for
more information.
3-74

Checking Coolant
The coolant surge tank is located in the engine
compartment on the passenger’s side of the vehicle.
SeeEngine Compartment Overview on page 5-14
for more information on location.
{CAUTION:
Turning the surge tank pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. Never turn the surge tank pressure
cap — even a little — when the engine and
radiator are hot.
The vehicle must be on a level surface. When your
engine is cold, the coolant level should be at the
FULL COLD mark on the coolant surge tank.
If your vehicle has a low coolant sensor and the
LOW COOLANT LEVEL message comes on and
stays on, it means you are low on engine coolant.
See “LOW COOLANT LEVEL” underDIC Warnings
and Messages on page 3-66.
Adding Coolant
If you need more coolant, add the proper DEX-COOL®
coolant mixture at the surge tank, but only when the
engine is cool. SeeCooling System on page 5-35
for more information.
{CAUTION:
You can be burned if you spill coolant on hot
engine parts. Coolant contains ethylene glycol,
and it will burn if the engine parts are hot
enough. Do not spill coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand-tight and fully seated.
5-31