2007 GMC ENVOY sensor

Electronically Controlled Air
Suspension System
Your vehicle may be equipped with an electronically
controlled air suspension system that automatically
keeps your vehicle level as you load and unload.
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.
During this time, the indicator light on the air
inator switch will be ashing.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.
You may hear the compressor operating when you
load your vehicle, 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.
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How to Check
Use a good quality pocket-type gage to check
tire pressure. You cannot tell if your tires are
properly inated simply by looking at them. Radial
tires may look properly inated even when
they’re underinated. Check the tire’s ination
pressure when the tires are cold. Cold means your
vehicle has been sitting for at least three hours
or driven no more than 1 mile (1.6 km).
Remove the valve cap from the tire valve stem.
Press the tire gage rmly onto the valve to
get a pressure measurement. If the cold tire
ination pressure matches the recommended
pressure on the tire and loading information label,
no further adjustment is necessary. If the
pressure is low, add air until you reach the
recommended amount.
If you overll the tire, release air by pushing on
the metal stem in the center of the tire valve.
Recheck the tire pressure with the tire gage.
Be sure to put the valve caps back on the valve
stems. They help prevent leaks by keeping
out dirt and moisture.
Tire Pressure Monitor System
The Tire Pressure Monitor System (TPMS) uses
radio and sensor technology to check tire pressure
levels. TPMS sensors are mounted on each tire
and wheel assembly, except the spare tire.
The TPMS sensors monitor the air pressure in
your vehicle’s tires and transmit tire pressure
readings to a receiver located in the vehicle.
The TPMS is designed to alert the driver if a low
tire pressure condition exists. If your vehicle
has the Driver Information Center (DIC) steering
wheel control buttons, tire pressure levels
may also be checked through the DIC. See “Tire
Pressures” underDIC Operation and Displays
on page 219.
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Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure,
even if under-ination has not reached the level to
trigger illumination of the TPMS low tire pressure
telltale.
Your vehicle has also been equipped with a TPMS
malfunction indicator to indicate when the system is
not operating properly. The TPMS malfunction
indicator is combined with the low tire pressure
telltale. When the system detects a malfunction, the
telltale will ash for approximately one minute and
then remain continuously illuminated. This
sequence will continue upon subsequent vehicle
start-ups as long as the malfunction exists.
When the malfunction indicator is illuminated, the
system may not be able to detect or signal low
tire pressure as intended. TPMS malfunctions may
occur for a variety of reasons, including the
installation of replacement or alternate tires or
wheels on the vehicle that prevent the TPMS from
functioning properly. Always check the TPMS
malfunction telltale after replacing one or more
tires or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels allow
the TPMS to continue to function properly.The Tire and Loading Information label (tire
information placard) shows the size of your
vehicle’s original tires and the correct ination
pressure for your vehicle’s tires when they
are cold. SeeInation - Tire Pressure on
page 447. For the location of the tire and loading
information label, seeLoading Your Vehicle
on page 349.
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 453andTires on page 439.
Notice:Do not use a tire sealant if your
vehicle has Tire Pressure Monitors. The liquid
sealant can damage the tire pressure monitor
sensors.
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TPMS Sensor Identication Codes
Each TPMS sensor has a unique identication
code. Any time you replace one or more of
the TPMS sensors or rotate the vehicle’s tires, 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’s side front tire, passenger’s side
front tire, passenger’s side rear tire, and driver’s
side rear tire using a TPMS diagnostic tool.
See your dealer for service.
The TPMS sensors may also be matched to each
tire/wheel position by increasing or decreasing
the tire’s air pressure. When increasing the tire’s
pressure, do not exceed the maximum ination
pressure indicated on the tire’s sidewall.
You will have two minutes to match the rst
tire/wheel position, and ve minutes overall to
match all four tire/wheel positions. If it takes longer
than two minutes, to match the rst tire and
wheel, or more than ve minutes to match all
four tire and wheel positions the matching
process stops and you will need to start over.The TPMS sensor matching process is
outlined below:
1. Set the parking brake.
2. Turn the ignition switch to RUN with the
engine off.
3. Turn the headlamp control from off to parking
lamps four times within three seconds. A
double horn chirp will sound and the TPMS
low tire warning light will begin to ash.
The double horn chirp and ashing TPMS
warning light indicate that the TPMS matching
process has started. The TPMS warning
light should continue ashing throughout the
matching procedure.
4. Start with the driver’s side front tire.
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5. Remove the valve cap from the valve cap stem.
Activate the TPMS sensor by increasing or
decreasing the tire’s air pressure for
10 seconds, then stop and listen for a single
horn chirp. The single horn chirp should sound
within 15 seconds, conrming that the sensor
identication code has been matched to this
tire and wheel position. If you do not hear the
conrming single horn chirp, you will need to
start over with step number one. To let
air-pressure out of a tire you can use the
pointed end of the valve cap, a pencil-style air
pressure gage, or a key.
6. Proceed to the passenger’s side front tire,
and repeat the procedure in Step 5.
7. Proceed to the passenger’s side rear tire,
and repeat the procedure in Step 5.
8. Proceed to the driver’s side rear tire, and
repeat the procedure in Step 5.9. After hearing the conrming horn chirp for
the driver’s side rear tire, check to see if
the TPMS warning light is still ashing. If yes,
turn the ignition switch to LOCK to exit the
sensor matching process. If the TPMS warning
light is not ashing, the ve minute time
limit has passed and you will need to start
the process over beginning with Step 1.
10. Set all four tires to the recommended air
pressure level as indicated on the Tire
and Loading Information label.
11. Put the valve caps back on the valve stems
The spare tire does not have a TPMS sensor.
If you replace one of the road tires with the spare,
the SERVICE TIRE MONITOR message will be
displayed on the DIC screen. This message should
go off once you re-install the road tire containing
the TPMS sensor.
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When rotating your tires, always use the correct
rotation pattern shown here.
After the tires have been rotated, adjust the front
and rear ination pressures as shown on the
Tire and Loading Information label. SeeLoading
Your Vehicle on page 349, for an example of
the label and its location on your vehicle.
The Tire Pressure Monitor System (TPMS)
sensors will need to be reset after a tire rotation.
See “TPMS Sensor Identication Codes” under
Tire Pressure Monitor System on page 448.Make certain that all wheel nuts are properly
tightened. See “Wheel Nut Torque” under
Capacities and Specications on page 502.
{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after time. The wheel could
come off and cause an accident. When
you change a wheel, remove any rust or
dirt from places where the wheel attaches
to the vehicle. In an emergency, you can
use a cloth or a paper towel to do this;
but be sure to use a scraper or wire brush
later, if needed, to get all the rust or dirt
off. SeeChanging a Flat Tire on page 465.
454

Fuses Usage
5Driver’s Side High-Beam
Headlamp
6Driver’s Side Low-Beam
Headlamp
7 Windshield Wiper
8 Active Transfer Case
9 Windshield Washer
10 Powertrain Control Module B
11 Fog Lamps
12 Stoplamp
13 Cigarette Lighter
15 Electric Adjustable Pedals
16Truck Body Controller,
Ignition 1
17 Crank
18 Airbag
19 Trailer Electric Brake
20 Cooling Fan
21 Horn
22 Ignition E
23 Electronic Throttle ControlFuses Usage
24Instrument Panel Cluster,
Driver Information Center
25Automatic Shift Lock Control
System
26Transmission Control Module
Canister
27 Backup
28 Powertrain Control Module 1
29 Oxygen Sensor
30 Air Conditioning
31 Truck Body Controller 1
32 Trailer
33 Anti-lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Blower
50 Passenger’s Side Trailer Turn
51 Driver’s Side Trailer Turn
52 Hazard Flashers
53 Headlamp Driver Module
54Air Injection Reactor (AIR)
Solenoid
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Fuses Usage
5Driver’s Side High-Beam
Headlamp
6Driver’s Side Low-Beam
Headlamp
7 Windshield Wiper
8 Active Transfer Case
9 Windshield Washer
10 Powertrain Control Module B
11 Fog Lamps
12 Stoplamp
13 Cigarette Lighter
14 Ignition Coils
15Transmission Control Module
(TCM) Canister Vent
16 Truck Body Controller, Ignition 1
17 Crank
18 Airbag
19 Trailer Electric Brake
20 Cooling Fan
21 Horn
22 Ignition E
23 Electronic Throttle Control
24Instrument Panel Cluster,
Driver Information CenterFuses Usage
25Automatic Shift Lock Control
System
26 Engine 1
27 Backup
28 Powertrain Control Module 1
29 Powertrain Control Module
30 Air Conditioning
31 Injector Bank A
32 Trailer
33 Anti-lock Brakes (ABS)
34 Ignition A
35 Blower Motor
36 Ignition B
50 Passenger’s Side Trailer Turn
51 Driver’s Side Trailer Turn
52 Hazard Flashers
53 Transmission
54 Oxygen Sensor Bank B
55 Oxygen Sensor Bank A
56 Injector Bank B
57 Headlamp Driver Module
58 Truck Body Controller 1
59 Electric Adjustable Pedal
498