ignition GMC ENVOY 2009 Repair Manual

Four-Wheel-Drive Vehicles
Four-wheel-drive vehicles can be dinghy towed if the
proper procedures are followed. The transmission has no
provisions for internal lubrication while being towed, so it
is important that all the steps listed in this manual are
followed to dinghy tow a four-wheel-drive vehicle.Use the following procedure to dinghy tow a
four-wheel-drive vehicle:
1. Position the vehicle being towed behind the tow
vehicle and shift the transmission to P (Park).
2. Turn the engine off, but leave the ignition in the
ACC/ACCESSORY position.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to the tow
vehicle.
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{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer case
into N (Neutral) can cause the vehicle to roll even if
the transmission is in P (Park). The driver or others
could be injured. Make sure the parking brake
is rmly set before the transfer case is shifted to
N (Neutral).
5. Shift the transfer case to Neutral. See “Shifting into
Neutral” underFour-Wheel Drive on page 2-28.
6. Release the parking brake only after the vehicle
being towed is rmly attached to the towing vehicle.
7. Turn the ignition to LOCK/OFF and remove the
key — the steering wheel will still turn.
After towing, see “Shifting Out of Neutral” under
Four-Wheel Drive on page 2-28.
Dolly Towing
Front Towing (Front Wheels Off the
Ground)
Two-Wheel-Drive Vehicles
Notice:If a two-wheel-drive vehicle is towed with
the rear wheels on the ground, the transmission
could be damaged. The repairs would not be
covered by the vehicle warranty. Never tow the
vehicle with the rear wheels on the ground.
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Four-Wheel-Drive Vehicles
Use the following procedure to dolly tow a
four-wheel-drive vehicle from the front with the
rear wheels on the ground:
1. Attach the dolly to the tow vehicle following the
dolly manufacturer’s instructions.
2. Drive the front wheels onto the dolly.
3. Shift the transmission to P (Park).
4. Firmly set the parking brake.
{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer case
into N (Neutral) can cause the vehicle to roll even
if the transmission is in P (Park). The driver or
others could be injured. Make sure the parking
brake is rmly set before the transfer case is
shifted to N (Neutral).
5. Shift the transfer case to Neutral. See “Shifting into
Neutral” underFour-Wheel Drive on page 2-28.
6. Secure the vehicle to the dolly following the
manufacturer’s instructions.
7. Release the parking brake only after the vehicle
being towed is rmly attached to the dolly.
8. Turn the ignition to LOCK/OFF.
After towing, see “Shifting Out of Neutral” under
Four-Wheel Drive on page 2-28.
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Rear Towing (Rear Wheels Off the
Ground)Two-Wheel-Drive Vehicles
Use the following procedure to dolly tow a
two-wheel-drive vehicle from the rear:
1. Attach the dolly to the tow vehicle following the
dolly manufacturer’s instructions.
2. Drive the rear wheels onto the dolly.
3. Firmly set the parking brake. SeeParking Brake on
page 2-33.
4. Put the transmission in P (Park).
5. Secure the vehicle to the dolly following the
manufacturer’s instructions.
6. Use an adequate clamping device designed for
towing to ensure that the front wheels are locked
into the straight position.
7. Turn the ignition to LOCK/OFF.
4-43

Four-Wheel-Drive Vehicles
Use the following procedure to dolly tow a
four-wheel-drive vehicle from the rear:
1. Attach the dolly to the tow vehicle following the
dolly manufacturer’s instructions.
2. Drive the rear wheels onto the dolly.
3. Firmly set the parking brake. SeeParking Brake on
page 2-33.
4. Put the transmission in P (Park).
5. Secure the vehicle to the dolly following the
manufacturer’s instructions.
6. Use an adequate clamping device designed for
towing to ensure that the front wheels are locked
into the straight position.{CAUTION:
Shifting a four-wheel-drive vehicle’s transfer case
into N (Neutral) can cause the vehicle to roll even
if the transmission is in P (Park). The driver or
others could be injured. Make sure the parking
brake is rmly set before the transfer case is
shifted to N (Neutral).
7. Shift the transfer case to Neutral. See “Shifting into
Neutral” underFour-Wheel Drive on page 2-28.
8. Turn the ignition to LOCK/OFF.
After towing, see “Shifting Out of Neutral” under
Four-Wheel Drive on page 2-28.
4-44

Electronically Controlled Air
Suspension System
With this feature, an electronically controlled air
suspension system automatically keeps the vehicle level
as it is loaded and unloaded. The system includes a
compressor, two height sensors and two air springs
supporting the rear axle.
The system also has an internal clock to prevent
overheating if the inator is used for prolonged periods.
If the system overheats, all leveling function stops
until the system cools down.
The ignition has to be on for the system to inate, in
order to raise the vehicle to the standard ride height after
loading. The system can lower the vehicle to the standard
ride height after unloading with the ignition on and also for
up to 30 minutes after the ignition has been turned off.
The compressor may be heard while it is operating when
the vehicle is being loaded, and periodically as the
system adjusts the vehicle to the standard ride height.
Load leveling will not function normally with the
inator hose attached to the inator outlet. Remove the
inator hose from the outlet during loading and
unloading.
If the vehicle is parked for an extended period of time,
some bleed down of the suspension is normal. Upon
starting the vehicle, proper height will be achieved.
Overload Protection
The air suspension system is equipped with overload
protection. Overload protection is designed to protect
the air suspension system, and it is an indicator to the
driver that the vehicle is overloaded. When the overload
protection mode is on, it will not allow damage to the
air compressor. However, do not overload the vehicle.
SeeLoading the Vehicle on page 4-31.
If the suspension remains at a low height, the rear
axle load has exceeded GAWR (Gross Axle Weight
Rating). When the overload protection mode is activated,
the compressor operates for about 30 seconds to one
minute without raising the vehicle depending on the
amount of overload. This will continue each time
the ignition is turned on until the rear axle load is
reduced below GAWR.
Indicator Light
The indicator light on the inator switch in the rear
passenger compartment also serves as an indicator for
internal system error. If the indicator light is ashing
without the load leveling function or the inator being
active, turn off the ignition. The next day turn on
the ignition and check the indicator light. The vehicle
can be driven with the light ashing, but if it is, the
vehicle should be serviced as soon as possible.
4-45

How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
the engine oil and lter based on vehicle use. Whenever
the oil is changed, reset the system so it can calculate
when the next oil change is required. If a situation occurs
where the oil is changed prior to a change engine oil light
or CHANGE ENGINE OIL message being turned on,
reset the system.
To reset the Engine Oil Life System:
1. Turn the ignition key to ON/RUN with the
engine off.
2. Fully press and release the accelerator pedal slowly
three times within ve seconds.
The change engine oil light will ash while the
system is resetting.
3. When the light stops ashing, turn the key to
LOCK/OFF.
If the light/message comes back on when the vehicle is
started, the engine oil life system has not reset.
Repeat the procedure.
What to Do with Used Oil
Used engine oil contains certain elements that can be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
lter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Recycle it by taking it to a
place that collects used oil.
5-19

Notice:If you leave the radio or other accessories
on during the jump starting procedure, they could be
damaged. The repairs would not be covered by the
warranty. Always turn off the radio and other
accessories when jump starting the vehicle.
3. Turn off the ignition on both vehicles. Unplug
unnecessary accessories plugged into the cigarette
lighter or the accessory power outlets, if equipped.
Turn off the radio and all lamps that are not
needed. This will avoid sparks and help to save
both batteries. And it could save the radio!
4. Open both hoods and locate the batteries. Find
the positive (+) and negative (−) terminals on
each battery. Your vehicle has a remote negative (−)
jump starting terminal. You should always use
this remote terminal instead of the terminal on the
battery. The remote negative (−) terminal is
located on the front engine lift bracket on vehicles
with the 4.2L L6 engine or the engine accessory
drive bracket for vehicles with the 5.3L V8 engine,
and is marked GND (Ground). SeeEngine
Compartment Overview on page 5-12for more
information on location.
{CAUTION:
Using a match near a battery can cause battery
gas to explode. People have been hurt doing this,
and some have been blinded. Use a ashlight if
you need more light.
Be sure the battery has enough water. You do not
need to add water to the battery installed in your
new vehicle. But if a battery has ller caps, be
sure the right amount of uid is there. If it is low,
add water to take care of that rst. If you do not,
explosive gas could be present.
Battery uid contains acid that can burn you.
Do not get it on you. If you accidentally get it in
your eyes or on your skin, ush the place with
water and get medical help immediately.
5-40

At the same time a message to check the pressure in a
specic tire appears on the Driver Information Center
(DIC) display. The low tire pressure warning light and the
DIC warning message come on at each ignition cycle
until the tires are inated to the correct ination pressure.
Using the DIC, tire pressure levels can be viewed by the
driver. For additional information and details about the
DIC operation and displays seeDIC Operation and
Displays on page 3-48andDIC Warnings and Messages
on page 3-51.
The low tire pressure warning light may come on in
cool weather when the vehicle is rst started, and then
turn off as you start to drive. This could be an early
indicator that the air pressure in the tire(s) is low and
needs to be inated to the proper pressure.
A Tire and Loading Information label, attached to your
vehicle, shows the size of your vehicle’s original
equipment tires and the correct ination pressure for
your vehicle’s tires when they are cold. SeeLoading theVehicle on page 4-31, for an example of the Tire and
Loading Information label and its location on your
vehicle. Also seeInflation - Tire Pressure on page 5-60.
Your vehicle’s TPMS can alert you about a low tire
pressure condition but it does not replace normal tire
maintenance. SeeTire Inspection and Rotation on
page 5-68andTires on page 5-53.
Notice:Using non-approved tire sealants could
damage the Tire Pressure Monitor System (TPMS)
sensors. TPMS sensor damage caused by using
an incorrect tire sealant is not covered by the
vehicle warranty. Always use the GM approved tire
sealant available through your dealer/retailer.
Factory-installed Tire Inator Kits use a GM approved
liquid tire sealant. Using non-approved tire sealants
could damage the TPMS sensors. See Tire Sealant and
Compressor Kit for information regarding the inator
kit materials and instructions.
5-65

TPMS Malfunction Light and Message
The TPMS will not function properly if one or more of the
TPMS sensors are missing or inoperable. When the
system detects a malfunction, the low tire warning light
ashes for about one minute and then stays on for the
remainder of the ignition cycle. A DIC warning message
is also displayed. The low tire warning light and DIC
warning message come on at each ignition cycle until the
problem is corrected. Some of the conditions that can
cause the malfunction light and DIC message to come
on are:
One of the road tires has been replaced with the
spare tire, if the vehicle has one. The spare tire does
not have a TPMS sensor. The TPMS malfunction
light and DIC message should go off once you
re-install the road tire containing the TPMS sensor.
The TPMS sensor matching process was started but
not completed or not completed successfully after
rotating the vehicle’s tires. The DIC message and
TPMS malfunction light should go off once the TPMS
sensor matching process is performed successfully.
See “TPMS Sensor Matching Process” later in this
section.
One or more TPMS sensors are missing or
damaged. The DIC message and the TPMS
malfunction light should go off when the TPMSsensors are installed and the sensor matching
process is performed successfully. See your
dealer/retailer for service.
Replacement tires or wheels do not match your
vehicle’s original equipment tires or wheels. Tires
and wheels other than those recommended for your
vehicle could prevent the TPMS from functioning
properly. SeeBuying New Tires on page 5-70.
Operating electronic devices or being near facilities
using radio wave frequencies similar to the TPMS
could cause the TPMS sensors to malfunction.
If the TPMS is not functioning it cannot detect or signal a
low tire condition. See your dealer/retailer for service if
the TPMS malfunction light and DIC message come on
and stay on.
TPMS Sensor Matching Process
Each TPMS sensor has a unique identication code. Any
time you rotate your vehicle’s tires or replace one or more
of the TPMS sensors, the identication codes will need to
be matched to the new tire/wheel position. The sensors
are matched to the tire/wheel positions in the following
order: driver side front tire, passenger side front tire,
passenger side rear tire, and driver side rear tire using
a TPMS diagnostic tool. See your dealer/retailer for
service.
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