2008 CHEVROLET SILVERADO ECU

If a child restraint has been installed and the on
indicator is lit, turn the vehicle off. Remove the child
restraint from the vehicle and reinstall the child restraint
following the child restraint manufacturer’s directions
and refer toSecuring a Child Restraint in the Right Front
Seat Position (With Airbag Off Switch) on page 1-57
orSecuring a Child Restraint in the Right Front Seat
Position (With Passenger Sensing System) on page 1-62
orSecuring a Child Restraint in the Right Front Seat
Position (Heavy Duty Crew Cab Only) on page 1-66.
If, after reinstalling the child restraint and restarting the
vehicle, the on indicator is still lit, check to make sure that
the vehicle’s seatback is not pressing the child restraint
into the seat cushion. If this happens, slightly recline
the vehicle’s seatback and adjust the seat cushion if
possible. Also make sure the child restraint is not trapped
under the vehicle head restraint. If this happens, adjust
the head restraint. SeeHead Restraints on page 1-11.
Remove any additional material from the seat such as
blankets, cushions, seat covers, seat heaters, or seat
massagers before reinstalling or securing the child
restraint.If the on indicator is still lit, secure the child in the child
restraint in a rear seat position in the vehicle, and
check with your dealer/retailer. If no rear seat is
available, do not install a child restraint in this vehicle,
and check with your dealer/retailer.
The passenger sensing system is designed to enable
(may inate) the right front passenger’s frontal airbag
anytime the system senses that a person of adult size is
sitting properly in the right front passenger’s seat. When
the passenger sensing system has allowed the airbag to
be enabled, the on indicator will light and stay lit to remind
you that the airbag is active.
For some children who have outgrown child restraints
and for very small adults, the passenger sensing system
may or may not turn off the right front passenger’s frontal
airbag, depending upon the person’s seating posture
and body build. Everyone in your vehicle who has
outgrown child restraints should wear a safety belt
properly — whether or not there is an airbag for that
person.
1-83

In addition, your vehicle may have a passenger
sensing system for the right front passenger’s
position, which includes sensors that are part of the
passenger’s seat. The passenger sensing system
may not operate properly if the original seat trim is
replaced with non-GM covers, upholstery or trim, or
with GM covers, upholstery or trim designed for a
different vehicle. Any object, such as an aftermarket
seat heater or a comfort enhancing pad or device,
installed under or on top of the seat fabric, could also
interfere with the operation of the passenger sensing
system. This could either prevent proper deployment
of the passenger airbag(s) or prevent the passenger
sensing system from properly turning off the
passenger airbag(s). SeePassenger Sensing
System on page 1-81.
If you have any questions about this, you should
contact Customer Assistance before you modify
your vehicle. The phone numbers and addresses
for Customer Assistance are in Step Two of
the Customer Satisfaction Procedure in this manual.
SeeCustomer Satisfaction Procedure on page 7-2.
If your vehicle has rollover roof-rail airbags, see
Different Size Tires and Wheels on page 5-88
for additional important information.Q:What if I added a snow plow? Will it keep the
airbags from working properly?
A:We have designed our airbag systems to work
properly under a wide range of conditions, including
snow plowing with vehicles that have the optional
Snow Plow Prep Package (RPO VYU). But do
not change or defeat the snow plow’s “tripping
mechanism.” If you do, it can damage your snow
plow and your vehicle, and it may cause an airbag
ination.
Q:Because I have a disability, I have to get my
vehicle modied. How can I nd out whether
this will affect my airbag system?
A:If you have questions, call Customer Assistance.
The phone numbers and addresses for Customer
Assistance are in Step Two of the Customer
Satisfaction Procedure in this manual. See
Customer Satisfaction Procedure on page 7-2.
In addition, your dealer/retailer and the service manual
have information about the location of the airbag
sensors, sensing and diagnostic module and airbag
wiring.
1-87

Keys...............................................................2-3
Remote Keyless Entry (RKE) System................2-4
Remote Keyless Entry (RKE) System
Operation...................................................2-5
Remote Vehicle Start......................................2-7
Doors and Locks............................................2-10
Door Locks..................................................2-10
Power Door Locks........................................2-10
Delayed Locking...........................................2-11
Programmable Automatic Door Locks..............2-11
Rear Door Security Locks..............................2-11
Lockout Protection........................................2-12
Rear Doors..................................................2-12
Tailgate.......................................................2-13
Windows........................................................2-15
Manual Windows..........................................2-15
Power Windows............................................2-16
Power Sliding Rear Window...........................2-17
Sun Visors...................................................2-18
Theft-Deterrent Systems..................................2-18
Content Theft-Deterrent.................................2-18
PASS-Key
®III+ Electronic Immobilizer.............2-20
PASS-Key®III+ Electronic Immobilizer
Operation.................................................2-20Starting and Operating Your Vehicle................2-22
New Vehicle Break-In....................................2-22
Ignition Positions..........................................2-22
Retained Accessory Power (RAP)...................2-24
Starting the Engine.......................................2-24
Fast Idle System..........................................2-25
Adjustable Throttle and Brake Pedal................2-26
Engine Coolant Heater..................................2-27
Active Fuel Management™.............................2-28
Automatic Transmission Operation...................2-28
Tow/Haul Mode............................................2-34
Four-Wheel Drive..........................................2-36
Parking Brake..............................................2-50
Shifting Into Park..........................................2-51
Shifting Out of Park......................................2-53
Parking Over Things That Burn.......................2-53
Engine Exhaust............................................2-54
Running the Vehicle While Parked..................2-54
Mirrors...........................................................2-56
Manual Rearview Mirror.................................2-56
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and Temperature
Display....................................................2-56
Automatic Dimming Rearview Mirror with
Compass and Temperature Display..............2-58
Section 2 Features and Controls
2-1

Delayed Locking
When locking the doors with the power lock switch or
the Remote Keyless Entry (RKE) transmitter and a door
is open, the doors will lock ve seconds after the last
door is closed. You will hear three chimes to signal that
the delayed locking feature is in use.
Pressing the power lock switch twice or the lock button
on the RKE transmitter twice will override the delayed
locking feature and immediately lock all the doors.
This feature will not operate if the key is in the ignition.
You can program this feature using the Driver
Information Center (DIC). See DELAY DOOR LOCK
underDIC Vehicle Customization (With DIC Buttons)
on page 3-76.
Programmable Automatic Door
Locks
Vehicles with an automatic lock/unlock feature enable
you to program the vehicle’s power door locks. You can
program this feature through the Driver Information
Center (DIC). SeeDIC Vehicle Customization (With DIC
Buttons) on page 3-76for more information on DIC
programming.
Rear Door Security Locks
Your vehicle has rear door security locks. These
prevent passengers from opening the rear doors from
the inside.
The rear door security
locks are located on the
inside edge of each
rear door.
The rear doors must be open to access them.
The label showing lock and unlock positions is located
near the lock.
To set the locks, do the following:
1. Insert the key into the security lock slot and turn it
so the slot is in the horizontal position.
2. Close the door.
2-11

When you want to open a rear door when the security
lock is on, do the following:
1. Unlock the door by lifting the rear door manual lock,
using the power door lock switch, or the Remote
Keyless Entry (RKE) transmitter, if the vehicle
has one.
2. Open the door from the outside.
To cancel the rear door security lock, do the following:
1. Unlock the door and open it from the outside.
2. Insert the key into the security lock slot and turn it
so the slot is in the vertical position.
Lockout Protection
This feature protects you from locking the key in the
vehicle when the key is in the ignition and a front door
is open.
If the driver’s side power door lock switch is pressed
when the driver’s door is open and the key is in the
ignition, all of the doors will lock and then the driver’s
door will unlock.
If the passenger’s side power door lock switch is
pressed when the front passenger’s door is open and
the key is in the ignition, all of the doors will lock
and then the front passenger’s door will unlock.
Rear Doors
Extended Cab
Your vehicle may have a rear access door(s) that allows
easier access to the rear area of the extended cab.
To open a rear access
door from the outside,
rst open the front door.
Then, use the handle
located on the front edge
of the rear access door
to open it.
You must fully close a rear access door before you can
close the front door.
2-12

To open a rear access
door from the inside, the
front door must be opened
rst. Then, use the handle
located on the inside of the
rear access door to open.
Crew Cabs
If your vehicle is a crew cab, you can open your doors
from the inside or outside. Your vehicle may also
have a feature which prevents children from opening the
rear doors. SeeRear Door Security Locks on page 2-11
for more information.
Tailgate
{CAUTION:
It is extremely dangerous to ride on the
tailgate, even when the vehicle is operated at
low speeds. People riding on the tailgate can
easily lose their balance and fall in response
to vehicle maneuvers. Falling from a moving
vehicle may result in serious injuries or death.
Do not allow people to ride on the tailgate.
Be sure everyone in your vehicle is in a seat
and using a safety belt properly.
On vehicles with a lock on the tailgate, use the key to
lock or unlock the tailgate.
Open the tailgate by lifting up on its handle while pulling
the tailgate toward you.
To shut the tailgate, rmly push it upward until it
latches.
After you put the tailgate back up, pull it back towards
you to be sure it latches securely.
2-13

Tailgate Removal
The tailgate can be removed to allow for different
loading situations. Although the tailgate can be removed
without assistance, you may want someone to assist
you with the removal to avoid possible damage to
the vehicle.
To remove the tailgate, do the following:
1. Raise the tailgate
slightly and release
both retaining cable
clips. To release the
retaining cable clips, lift
the cable so it points
straight out. Lift the clip
over the bolt, and push
the cable forward then
rotate down.2. With the tailgate about halfway open, lift the right
edge of the tailgate from the lower pivot.
On vehicles with the tailgate assist feature, raise
the tailgate nearly all the way to the closed position
prior to removing the left edge.
3. Move the tailgate to the right to release the
left edge.
Reverse this procedure to reinstall the tailgate.
Make sure the tailgate is secure.
2-14

Sun Visors
Pull the sun visor down to block glare. Swing the sun
visor to the side to cover the side window.
The passenger’s side sun visor may have a vanity
mirror.
Theft-Deterrent Systems
Vehicle theft is big business, especially in some cities.
This vehicle has theft-deterrent features, however,
they do not make it impossible to steal.
Content Theft-Deterrent
Your vehicle may have a content theft-deterrent alarm
system.
This is the security light.To arm the theft-deterrent system:
1. Open the door.
2. Lock the door with the Remote Keyless Entry (RKE)
transmitter. The security light should come on and
ash.
If the delayed locking feature is active, the alarm
will not be activated until all doors are closed
and the security light goes off.
3. Close all doors. The security light will stop ashing
and go off after approximately 30 seconds. The
content theft deterrent alarm is not armed until the
security light goes off.
If a locked door is opened without using the RKE
transmitter, a ten second pre-alarm will occur. The horn
will chirp and the lights will ash. If the key is not placed
in the ignition and turned to START or the door is not
unlocked by pressing the unlock button on the RKE
transmitter during the ten second pre-alarm, the alarm
will go off. Your vehicle’s headlamps will ash and the
horn will sound for about two minutes, then will turn off
to save the battery power.
2-18