2001 GMC YUKON Index

2-77 Traction Off Light (If Equipped)
If you have the Traction
Assist System, this light
should come on briefly
when you turn the ignition
to RUN.
If the light doesn't come on then, the system may
require service; have it fixed so it will be there to warn
you if the system is turned off.
If the TRACTION OFF light stays on, or comes on
when you're driving, there may be a problem with your
Traction Assist System and your vehicle may need
service. When this light is on, the system will not limit
wheel spin. Adjust your driving accordingly.
The TRACTION OFF light may come on for the
following reasons:

If you turn the system off by pressing the TAS on/off
button located to the left of the steering wheel, the
light will come on and stay on. To turn the system
back on, press the button again; the light should
go off.
If you move the shift lever to FIRST (1), the light
will come on and stay on to indicate that the Traction
Assist System is off. This is normal operation. To
turn the system back on, move the shift lever back to
a position other than FIRST (1); the light should go
off. See ªTraction Assist Systemº in the Index.

The light will come on and stay on if the TAS
automatic engagement feature has been turned off.
To turn the system on, press the TAS off/on button;
the light should go off. To turn the automatic
engagement feature back on, see ªTraction Assist
Systemº in the Index.

If the Traction Assist System is affected by an
anti
-lock brake system, Traction Assist System or
engine
-related problem, the system will turn off and
the light will come on. Have your vehicle serviced.

If the vehicle is driven over an extremely rough road,
the system will turn off and the light will come on.
The light will go off a few seconds after the rough
road conditions go away or when the vehicle comes
to a complete stop. This is normal operation.

2-80
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully install
the cap. See ªFilling Your Tankº in the Index. The
diagnostic system can determine if the fuel cap has been
left off or improperly installed. A loose or missing fuel
cap will allow fuel to evaporate into the atmosphere. A
few driving trips with the cap properly installed should
turn the light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The condition
will usually be corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?If so, be sure to fuel your vehicle with quality fuel. See
ªFuelº in the Index. Poor fuel quality will cause your
engine not to run as efficiently as designed. You may
notice this as stalling after start
-up, stalling when you put
the vehicle into gear, misfiring, hesitation on acceleration
or stumbling on acceleration. (These conditions may go
away once the engine is warmed up.) This will be detected
by the system and cause the light to turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
have your dealer or qualified service center check the
vehicle. Your dealer has the proper test equipment and
diagnostic tools to fix any mechanical or electrical
problems that may have developed.

2-82 Oil Pressure Gage
United States Canada
The oil pressure gage shows the engine oil pressure in
psi (pounds per square inch) when the engine is running.
Canadian vehicles indicate pressure in kPa (kilopascals).
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 some other problem causing
low oil pressure. Check your oil as soon as possible. See
ªCheck Eng Oil Pressureº and ªEngine Oilº in the Index.
CAUTION:
Don't keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches fire. You or others could be burned.
Check your oil as soon as possible and have your
vehicle serviced.
NOTICE:
Damage to your engine from neglected oil
problems can be costly and is not covered by
your warranty.

2-83 Cruise Light (If Equipped)
United States Canada
The CRUISE light comes on whenever you set your
cruise control. See ªCruise Controlº in the Index.
Tow/Haul Light
This message is displayed
when the tow/haul mode has
been activated.
For more information, see ªTow/Haul Modeº in
the Index.

2-86
The following situations can cause the transmission to
operate at higher temperatures:

Towing a trailer

Hot outside air temperatures

Hauling a large or heavy load

Low transmission fluid level

High transmission fluid level

Restricted air flow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures on
a frequent basis, see ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.
Trans Hot...Idle Engine
Your vehicle has a transmission over-temperature
display contained in the message center.
If this warning message is
displayed, pull the vehicle
off the roadway when it is
safe to do so.
Set the parking brake and place the transmission in
PARK (P). Idle the engine until the message center no
longer displays a message. If idling the engine does not turn
the warning message off after 10 to 15 minutes, contact
your nearest dealer or the GM Roadside Assistance Center.
See ªRoadside Assistanceº in the Index.
NOTICE:
If you keep driving your vehicle with the
transmission TRANS HOT...IDLE ENGINE
message displayed, you can damage the
transmission. This could lead to costly repairs
that may not be covered under your warranty.

2-87
The following situations can cause the transmission to
operate at higher temperatures:

Towing a trailer

Hot outside air temperatures

Hauling a heavy load

Low transmission fluid level

High transmission fluid level

Restricted air flow to the radiator and the auxiliary
transmission oil cooler (if equipped).
A temporary solution to hotter transmission operating
temperatures may be to let the transmission cool down.
If the transmission is operated at higher temperatures on
a frequent basis, see ªScheduled Maintenanceº in the
Index for the proper transmission maintenance intervals.
Low Coolant
This message is displayed
when the cooling system is
low on coolant.
The engine may overheat. See ªEngine Coolantº in the
Index and have your vehicle serviced as soon as you can.
Check Coolant Temp
This message is displayed
when the cooling system
temperature gets hot.
Check the coolant temperature gage and the coolant
level. See ªEngine Coolantº and ªEngine Coolant
Temperature Gageº in the Index. See ªEngine
Overheatingº in the Index for further information.
Engine Overheated
This message is displayed
when the cooling system
temperature gets too hot.
This message will be displayed after the air conditioning
system has automatically turned off for the engine
coolant protection mode. See ªEngine Overheatingº in
the Index for further information.

2-88 Reduced Engine Power
This message is displayed
when the cooling system
temperature gets too hot and
the engine further enters
the engine coolant
protection mode.
If your vehicle is equipped with the 8.1L engine, this
light may come on because of an electronic throttle
control system fault. See ªEngine Overheatingº in the
Index for further information.
Check Eng Oil Pressure
This message is displayed
when the engine oil pressure
is low.
See ªOil Pressure Gageº in the Index for more information.
Check Eng Oil Level
This message is displayed
when the engine oil level
is low.
Once oil is added, it may need time to drain and settle in
the engine before this message will turn off. It is best to
let the engine cool down (if it is hot) or warm up (if it is
cold) and cycle the ignition to be sure this message turns
off. Refer to the dipstick for the correct level.
See ªEngine Oilº in the Index on how to check the oil
level and for what type of oil to add.

2-89 Change Engine Oil
This message is displayed
when the engine oil needs to
be changed. The message
is only displayed for
15 seconds at the start of
each ignition cycle.
When you change the engine oil, be sure to reset the
Engine Oil Life System. See ªEngine Oil, When to
Changeº in the Index.
Security
This message is displayed
when the content
theft
-deterrent system
(if equipped) has been
activated and also monitors
the Passlock

System.
If the security message is displayed 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 GM dealer.
Service 4WD (If Equipped)
If the Service 4WD message
comes on, there may be a
problem with the automatic
transfer case 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.