ECU GMC SIERRA 2007 Repair Manual

{CAUTION:
If the on indicator comes on when you have
a rear-facing child restraint installed in the
right front passenger’s seat, it means that
the passenger sensing system has not
turned off the passenger’s frontal airbag. A
child in a rear-facing child restraint can be
seriously injured or killed if the right front
passenger’s airbag inates. This is
because the back of the rear-facing child
restraint would be very close to the
inating airbag. Do not use a rear-facing
child restraint in the right front passenger’s
seat if the airbag is turned on.
{CAUTION:
Even though the passenger sensing
system is designed to turn off the right
front passenger’s frontal airbag if the
system detects a rear-facing child
restraint, no system is fail-safe, and no
one can guarantee that an airbag will not
deploy under some unusual circumstance,
even though it is turned off. We
recommend that rear-facing child
restraints be secured in the rear seat,
even if the airbag is off.
If the word OFF or the off symbol is lit on the
airbag status indicator, it means that the
passenger sensing system has turned off the right
front passenger’s frontal airbag. SeePassenger
Sensing System on page 97for more on this,
including important safety information.
253

Oil Pressure Light
This light will come on
briey when you start
your engine.
{CAUTION:
Do not keep driving if the oil pressure is
low. If you do, your engine can become so
hot that it catches re. You or others could
be burned. Check your oil as soon as
possible and have your vehicle serviced.Notice:Lack of proper engine oil maintenance
may damage the engine. The repairs would
not be covered by your warranty. Always follow
the maintenance schedule in this manual for
changing engine oil.
That is a check to be sure the light works. If it
does not come on, be sure to have it xed so it will
be there to warn you if something goes wrong.
When the light comes on and stays on, it means
that oil is not owing through your engine
properly. You could be low on oil and you might
have some other system problem.Security Light
This light ashes when
the vehicle security
system is activated.
264

Radio Display Message Condition Action Required
No CAT Info Category Name
not availableNo category information is available at this time on this
channel. The system is working properly.
No Information No Text/Informational
message availableNo text or informational messages are available at this time
on this channel. The system is working properly.
CAT Not Found No channel available for
the chosen categoryThere are no channels available for the selected category.
The system is working properly.
XM TheftLocked Theft lock active The XM™ receiver in the vehicle could have previously
been in another vehicle. For security purposes, XM™
receivers cannot be swapped between vehicles. If this
message appears after having your vehicle serviced, check
with your dealer.
XM Radio ID Radio ID label (channel 0) If tuned to channel 0, this message alternates with the
XM™ Radio eight digit radio ID label. This label is needed
to activate the service.
Unknown Radio ID not known
(should only be if
hardware failure)If this message is received when tuned to channel 0, there
could be a receiver fault. Consult with your dealer/retailer.
Check XM Receivr Hardware failure If this message does not clear within a short period of time,
the receiver could have a fault. Consult with your
dealer/retailer.
XM Not Available XM™ Not Available If this message does not clear within a short period of time,
the receiver could have a fault. Consult with your
dealer/retailer.
354

Loading Your Vehicle for Off-Road
Driving
{CAUTION:
Cargo on the load oor piled higher
than the seatbacks can be thrown
forward during a sudden stop. You or
your passengers could be injured.
Keep cargo below the top of the
seatbacks.
Unsecured cargo on the load oor can
be tossed about when driving over
rough terrain. You or your passengers
can be struck by ying objects.
Secure the cargo properly.
Heavy loads on the roof raise the
vehicle’s center of gravity, making it
more likely to roll over. You can be
seriously or fatally injured if the
vehicle rolls over. Put heavy loads
inside the cargo area, not on the roof.
Keep cargo in the cargo area as far
forward and low as possible.There are some important things to remember
about how to load your vehicle.
The heaviest things should be on the load
oor and forward of the rear axle. Put
heavier items as far forward as you can.
Be sure the load is secured properly, so
driving on the off-road terrain does not
toss things around.
You will nd other important information in this
manual. SeeLoading Your Vehicle on page 425
andTires on page 550.
392

Winter Driving
Here are some tips for winter driving:
Have your vehicle in good shape for winter.
You may want to put winter emergency
supplies in your vehicle.
Also seeTires on page 550.Include an ice scraper, a small brush or broom, a
supply of windshield washer uid, a rag, some
winter outer clothing, a small shovel, a ashlight, a
red cloth, and reective warning triangles. And,
if you will be driving under severe conditions,
include a small bag of sand, a piece of old carpet,
or a couple of burlap bags to help provide
traction. Be sure you properly secure these items
in your vehicle.
Driving on Snow or Ice
Most of the time, those places where the tires
meet the road probably have good traction.
However, if there is snow or ice between the tires
and the road, you can have a very slippery
situation. You will have a lot less traction, or grip,
and will need to be very careful.
418

To nd out the actual loads on your front and rear
axles, you need to go to a weigh station and
weigh your vehicle. Your dealer can help you with
this. Be sure to spread out your load equally on
both sides of the centerline.
Never exceed the GVWR for your vehicle, or the
GAWR for either the front or rear axle.
The Certication/Tire label also contains important
information about your Front Axle Reserve
Capacity. See “What is front axle reserve capacity,
and how do I calculate it?” underAdding a
Snow Plow or Similar Equipment on page 432.
{CAUTION:
In the case of a sudden stop or collision,
things carried in the bed of your truck
could shift forward and come into the
passenger area, injuring you and others. If
you put things in the bed of your truck,
you should make sure they are properly
secured.
{CAUTION:
Do not load your vehicle any heavier than
the Gross Vehicle Weight Rating (GVWR),
or either the maximum front or rear Gross
Axle Weight Rating (GAWR). If you do,
parts on your vehicle can break, and it
can change the way your vehicle handles.
These could cause you to lose control
and crash. Also, overloading can shorten
the life of your vehicle.
Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
Using heavier suspension components to get
added durability might not change your weight
ratings. Ask your dealer to help you load
your vehicle the right way.
429

If you put things inside your vehicle — like
suitcases, tools, packages, or anything
else — they go as fast as the vehicle goes.
If you have to stop or turn quickly, or if there
is a crash, they will keep going.
{CAUTION:
Things you put inside your vehicle can
strike and injure people in a sudden stop
or turn, or in a crash.
Put things in the cargo area of your
vehicle. Try to spread the weight
evenly.
Never stack heavier things, like
suitcases, inside the vehicle so that
some of them are above the tops of
the seats.
CAUTION: (Continued)
CAUTION: (Continued)

Do not leave an unsecured child
restraint in your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down
unless you need to.
There is also important loading information for
off-road driving in this manual. See “Loading Your
Vehicle for Off-Road Driving“ underOff-Road
Driving on page 390.
430

Two-Tiered Loading
Depending on the model of your pick-up, you can
create an upper load platform by positioning
two or four 2 inches (5 cm) by 6 inches (15 cm)
wooden planks across the width of the pickup box.
The planks must be inserted in the pickup box
depressions. The length of the planks must allow
for at least a 3/4 inch (2 cm) bearing surface
on each end of the plank.
When using this upper load platform, be sure the
load is securely tied down to prevent it from
shifting. The load’s center of gravity should be
positioned in a zone over the rear axle. The zone
is located in the area between the front of each
wheel well and the rear of each wheel well.
The center of gravity height must not extend above
the top of the pickup box areboard.
Any load that extends beyond the vehicle’s
taillamp area must be properly marked according
to local laws and regulations.
Remember not to exceed the Gross Axle Weight
Rating (GAWR) of the front or rear axle.
Add-On Equipment
When you carry removable items, you may need
to put a limit on how many people you carry
inside your vehicle. Be sure to weigh your vehicle
before you buy and install the new equipment.
Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.
Remember not to exceed the Gross Axle Weight
Rating (GAWR) of the front or rear axle.
* Equipment Maximum Weight
Ladder Rack and Cargo 750 lbs (340 kg)
Cross Toolbox and Cargo 400 lbs (181 kg)
Side Boxes and Cargo 250 lbs per side (113 kg
per side)
* The combined weight for all rail-mounted equipment
should not exceed 1,000 lbs (454 kg).
431

Say, for example, you have a 700 lb (318 kg)
snow plow. The total weight of all occupants and
cargo inside the cab should not exceed 300 lb
(135 kg). This means that you may only be able to
carry one passenger. But, even this may be too
much if you have got other equipment already
adding to the weight of your vehicle.
Here are some guidelines for safely carrying a
snow plow on your vehicle:
Make sure the weight on the front and rear
axles does not exceed the axle rating for each.
For the front axle, if more cargo or passengers
must be carried, appropriate counter ballast
must be installed rear of the rear axle. Counter
ballast must be properly secured so it will not
move during driving.
Follow the snow plow manufacturer’s
recommendations regarding rear ballast. Rear
ballast may be required to ensure a proper front
and rear weight distribution ratio, even though
the actual weight at the front axle may be less
than the front axle rating.
The snow plow manufacturer or installer can
assist you in determining the amount of rear
ballast required, to help make sure your
snowplow/vehicle combination does not exceed
the GVW rating, the front and rear axle ratings,
and the front and rear weight distribution ratio.
The total vehicle must not exceed the GVW
rating.
433

You must weigh any accessories or other
equipment that you add to your vehicle. Then,
subtract this extra weight from the CWR. This extra
weight may shorten the center of gravity zone of
your vehicle. Your dealer can help you with this.
If your slide-in camper and its load weighs
less than the CWR, the center of gravity zone for
your vehicle may be larger.
Your dealer can help you make a good
vehicle-camper match and help you determine
the CWR.
After you have loaded your vehicle and camper,
drive to a weigh station and weigh the front
and rear wheels separately. This will tell you the
loads on the axles. The loads on the front and rear
axles should not be more than either of the
Gross Axle Weight Ratings (GAWR). The total of
the axle loads should not be more than the
Gross Vehicle Weight Rating (GVWR).
Open the driver’s door and look at the
Certication/Tire label to nd out your vehicle’s
GAWRs and GVWR.If your vehicle has gone over the weight ratings,
move or take out some things until all the
weight falls below the ratings.
Secure loose items to prevent weight shifts that
could affect the balance of your vehicle. When the
truck-camper is loaded, drive to a scale and
weigh on the front and on the rear wheels
separately to determine axle loads. Individual axle
loads should not exceed either of the gross
axle weight ratings (GAWR). The total axle loads
should not exceed your vehicle’s gross vehicle
weight rating (GVWR). These ratings are given on
the vehicle certication label attached to the
rear edge of the driver’s door. See
“Certication/Tire Label” underLoading Your
Vehicle on page 425. If weight ratings are
exceeded, move or remove items to bring all
weights below the ratings.
When you install and load your slide-in camper,
check the manufacturer’s instructions.
If you want more information on curb weights,
cargo weights, Cargo Weight Rating and the
correct center of gravity zone for your vehicle, your
dealer can help you. Just ask for a copy of
“Consumer Information, Truck-Camper Loading.”
438