2001 GMC ENVOY warning light

2-98
NOTICE:
Damage to your engine from neglected oil problems
can be costly and is not covered by your warranty.
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.
A reading in the low pressure zone may be caused by a
dangerously low oil level or other problems causing low
oil pressure.
Security Light
This light will come on
briefly when you turn
the key toward START.
The light will stay on
until the engine starts.
If the light flashes, the Passlock

system has entered a
tamper mode. If the vehicle fails to start, see ªPasslockº
in the Index.If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
system. Your vehicle will not be protected by Passlock,
and you should see your dealer.
Also, see ªContent Theft
-Deterrentº in the Index for
additional information regarding the SECURITY light.
Service Four-Wheel-Drive Warning Light
(If Equipped)
This light should come on
briefly when you turn on
the ignition, as a check to
show you it is working.
The SERVICE 4WD light comes on to indicate that
there may be a problem with the drive system and
service is required. Malfunctions can be indicated by the
system before any problem is apparent, which may
prevent serious damage to the vehicle. This system is
also designed to assist your service technician in
correctly diagnosing a malfunction.
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2-99
Tow/Haul Mode Light (If Equipped)
This light should come on
when the tow/haul mode
has been selected.
For more information, see ªTow/Haul Modeº in
the Index.
Check Gages Light
The CHECK GAGES light
will come on briefly when
you are starting the engine.
If the light comes on and stays on while you are driving,
check your coolant temperature and engine oil pressure
gages to see if they are in the warning zones.
Gate Ajar Light
If this light comes on, your
liftgate or liftglass is ajar.
Try closing the liftgate or
liftglass again. Never drive
with the liftgate or liftglass
even partially open.
Fuel Gage
United States Canada
When the ignition is on, the fuel gage tells you about
how much fuel you have remaining.
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4-8
Avoid needless heavy braking. Some people drive
in spurts
-- heavy acceleration followed by heavy
braking
-- rather than keeping pace with traffic.
This is a mistake. Your brakes may not have time
to cool between hard stops. Your brakes will wear
out much faster if you do a lot of heavy braking.
If you keep pace with the traffic and allow realistic
following distances, you will eliminate a lot of
unnecessary braking. That means better braking
and longer brake life.
If your engine ever stops while you're driving, brake
normally but don't pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and the
brake pedal will be harder to push.
Anti-Lock Brakes (ABS)
Your vehicle has anti-lock brakes (ABS). ABS is
an advanced electronic braking system that will help
prevent a braking skid.
When you start your engine and begin to drive away,
your anti
-lock brake system will check itself. You may
hear a momentary motor or clicking noise while this test
is going on. This is normal.
If there's a problem with
the anti
-lock brake system,
this warning light will stay
on. See ªAnti
-Lock Brake
System Warning Lightº in
the Index.
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4-32
Hydroplaning doesn't happen often. But it can if your
tires do not have much tread or if the pressure in one or
more is low. It can happen if a lot of water is standing on
the road. If you can see reflections from trees, telephone
poles or other vehicles, and raindrops ªdimpleº the
water's surface, there could be hydroplaning.
Hydroplaning usually happens at higher speeds.
There just isn't a hard and fast rule about hydroplaning.
The best advice is to slow down when it is raining.
Driving Through Deep Standing Water
NOTICE:
If you drive too quickly through deep puddles
or standing water, water can come in through
your engine's air intake and badly damage your
engine. Never drive through water that is slightly
lower than the underbody of your vehicle. If you
can't avoid deep puddles or standing water, drive
through them very slowly.
Driving Through Flowing Water
CAUTION:
Flowing or rushing water creates strong forces.
If you try to drive through flowing water, as you
might at a low water crossing, your vehicle can
be carried away. As little as six inches of flowing
water can carry away a smaller vehicle. If this
happens, you and the other vehicle occupants
could drown. Don't ignore police warning signs,
and otherwise be very cautious about trying to
drive through flowing water.
Some Other Rainy Weather Tips

Besides slowing down, allow some extra following
distance. And be especially careful when you pass
another vehicle. Allow yourself more clear room
ahead, and be prepared to have your view restricted
by road spray.

Have good tires with proper tread depth.
See ªTiresº in the Index.
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4-33
City Driving
One of the biggest problems with city streets is the
amount of traffic on them. You'll want to watch out for
what the other drivers are doing and pay attention to
traffic signals.Here are ways to increase your safety in city driving:

Know the best way to get to where you are
going. Get a city map and plan your trip into an
unknown part of the city just as you would for a
cross
-country trip.

Try to use the freeways that rim and crisscross
most large cities. You'll save time and energy.
See the next part, ªFreeway Driving.º

Treat a green light as a warning signal. A traffic light
is there because the corner is busy enough to need it.
When a light turns green, and just before you start
to move, check both ways for vehicles that have
not cleared the intersection or may be running the
red light.
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4-38
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.Include an ice scraper, a small brush or broom, a supply
of windshield washer fluid, a rag, some winter outer
clothing, a small shovel, a flashlight, a red cloth and
reflective 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 your tires meet
the road probably have good traction.
However, if there is snow or ice between your tires and
the road, you can have a very slippery situation. You'll
have a lot less traction or ªgripº and will need to be
very careful.
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5-3
Other Warning Devices
If you carry reflective triangles, you can set one up at
the side of the road about 300 feet (100 m) behind
your vehicle.
Jump Starting
If your battery has run down, you want to use another
vehicle and some jumper cables to start your vehicle.
But please use the following steps to do it safely.
CAUTION:
Batteries can hurt you. They can be
dangerous because:

They contain acid that can burn you.

They contain gas that can explode or ignite.

They contain enough electricity to burn you.
If you don't follow these steps exactly, some or
all of these things can hurt you.
NOTICE:
Ignoring these steps could result in costly damage
to your vehicle that wouldn't be covered by
your warranty.
The ACDelco battery in your vehicle has a
built
-in hydrometer. Do not charge, test or
jump start the battery if the hydrometer looks
clear or light yellow. Replace the battery when
there is a clear or light yellow hydrometer and
a cranking complaint.
Trying to start your vehicle by pushing or pulling
it won't work, and it could damage your vehicle.
1. Check the other vehicle. It must have a 12-volt
battery with a negative ground system.
NOTICE:
If the other system isn't a 12-volt system with a
negative ground, both vehicles can be damaged.
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6-24
When the differential is cold, add enough lubricant to raise
the level to 1/2 inch (12 mm) below the filler plug hole.
When the differential is at operating temperature
(warm), add enough lubricant to raise the level to the
bottom of the filler plug hole.
What to Use
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See ªRecommended Fluids and
Lubricantsº in the Index.
Engine Coolant
The cooling system in your vehicle is filled with
DEX
-COOL engine coolant. This coolant is designed
to remain in your vehicle for 5 years or 150,000 miles
(240 000 km), whichever occurs first, if you add only
DEX
-COOL extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, see ªEngine Overheatingº in
the Index.A 50/50 mixture of clean, drinkable water and
DEX
-COOL coolant will:

Give freezing protection down to
-34F (-37C).

Give boiling protection up to 265F (129C).

Protect against rust and corrosion.

Help keep the proper engine temperature.

Let the warning lights and gages work as they should.
NOTICE:
When adding coolant, it is important that you
use only DEX
-COOL (silicate-free) coolant.
If coolant other than DEX-COOL is added to
the system, premature engine, heater core or
radiator corrosion may result. In addition, the
engine coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever occurs first. Damage caused by the
use of coolant other than DEX
-COOL is not
covered by your new vehicle warranty.
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