2007 CHEVROLET TAHOE coolant level

2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 74°F
(23°C) temperature setting and allow about
20 minutes for the system to regulate. Use the
driver’s or passenger’s temperature buttons to
adjust the temperature setting as necessary. If
you choose the temperature setting of 60°F
(15°C), the system will remain at the maximum
cooling setting. If you choose the temperature
setting of 90°F (32°C), the system will remain
at the maximum heat setting. Choosing either
maximum setting will not cause the vehicle to
heat or cool any faster.
Be careful not to cover the solar sensor located on
the top of the instrument panel near the
windshield. This sensor regulates air temperature
based on sun load and also turns on your
headlamps. For more information on the solar
sensor, see “Sensors” later in this section.To avoid blowing cold air in cold weather, the
system will delay turning on the fan until warm air
is available. The length of delay depends on
the engine coolant temperature. Pressing the fan
switch will override this delay and change the
fan to a selected speed.
O(On/Off):Press this button to turn off the
climate control system. Outside air will still enter
the vehicle, and will be directed to the oor.
This direction can be changed by pressing the
mode button. Recirculation can be selected once
you have selected vent or bi-level mode. The
temperature can also be adjusted using either
temperature button. If you adjust the air delivery
mode or temperature settings with the system
off, the display will illuminate briey to show you
the settings and then return off. Press the
on/off button or the up down arrows on the fan
switch, the defrost button, AUTO button, or the air
conditioning button to turn the system on when
it is off.
233

DRIVER DOOR OPEN
This message displays and a chime sounds if the
driver’s door is not fully closed and the vehicle
is in a drive gear. Stop and turn off the vehicle,
check the door for obstructions, and close the door
again. Check to see if the message still appears
on the DIC.
ENGINE HOT A/C (Air Conditioning)
TURNED OFF
This message displays when the engine coolant
becomes hotter than the normal operating
temperature. SeeEngine Coolant Temperature
Gage on page 252. To avoid added strain on a hot
engine, the air conditioning compressor
automatically turns off. When the coolant
temperature returns to normal, the air conditioning
compressor turns back on. You can continue to
drive your vehicle.
If this message continues to appear, have the
system repaired by your dealer as soon as
possible to avoid damage to the engine.
ENGINE OIL LOW ADD OIL
If your vehicle has an oil level sensor, this
message displays if the oil level in the vehicle is
low. Check the oil level and correct it as
necessary. You may need to let the vehicle cool
or warm up and cycle the ignition to be sure
this message clears.
This message clears itself after 10 seconds, until
the next ignition cycle. SeeEngine Oil on
page 459for additional information.
ENGINE OVERHEATED IDLE ENGINE
Notice:If you drive your vehicle while the
engine is overheating, severe engine damage
may occur. If an overheat warning appears on
the instrument panel cluster and/or DIC, stop
the vehicle as soon as possible. SeeEngine
Overheating on page 473for more information.
This message displays when the engine coolant
temperature is too hot. Stop and allow the vehicle
to idle until it cools down. SeeEngine Coolant
Temperature Gage on page 252.
SeeOverheated Engine Protection Operating
Mode on page 476for information on driving to a
safe place in an emergency.
272

ENGINE OVERHEATED STOP ENGINE
Notice:If you drive your vehicle while the
engine is overheating, severe engine damage
may occur. If an overheat warning appears on
the instrument panel cluster and/or DIC, stop
the vehicle as soon as possible. SeeEngine
Overheating on page 473for more information.
This message displays and a chime sounds if the
engine cooling system reaches unsafe
temperatures for operation. Stop and turn off the
vehicle as soon as it is safe to do so to avoid
severe damage. This message clears when the
engine has cooled to a safe operating temperature.
ENGINE POWER IS REDUCED
This message displays and a chime sounds when
the cooling system temperature gets too hot
and the engine further enters the engine coolant
protection mode. SeeEngine Overheating on
page 473for further information.This message also displays when the vehicle’s
engine power is reduced. Reduced engine power
can affect the vehicle’s ability to accelerate. If
this message is on, but there is no reduction in
performance, proceed to your destination. The
performance may be reduced the next time the
vehicle is driven. The vehicle may be driven at a
reduced speed while this message is on, but
acceleration and speed may be reduced. Anytime
this message stays on, the vehicle should be taken
to your dealer for service as soon as possible.
FUEL LEVEL LOW
This message displays and a chime sounds if the
fuel level is low. Refuel as soon as possible.
SeeFuel Gage on page 259andFuel on page 446
for more information.
HOOD OPEN
This message displays and a chime sounds if the
hood is not fully closed. Stop and turn off the
vehicle, check the hood for obstructions, and close
the hood again. Check to see if the message
still appears on the DIC.
273

Turn Signals When Towing a Trailer
The arrows on your instrument panel will
ash whenever you signal a turn or lane change.
Properly hooked up, the trailer lamps will also
ash, telling other drivers you’re about to
turn, change lanes or stop.
When towing a trailer, the arrows on your
instrument panel will ash for turns even if the
bulbs on the trailer are burned out. Thus, you may
think drivers behind you are seeing your signal
when they are not. It’s important to check
occasionally to be sure the trailer bulbs are still
working.
Driving On Grades
Reduce speed and shift to a lower gearbefore
you start down a long or steep downgrade. If you
don’t shift down, you might have to use your
brakes so much that they would get hot and no
longer work well.You can tow in DRIVE (D). You may want to shift
the transmission to THIRD (3) or, if necessary,
a lower gear selection if the transmission shifts too
often (e.g., under heavy loads and/or hilly
conditions).
You may also want to activate the tow/haul mode
if the transmission shifts too often. See “Tow/Haul
Mode” earlier in this section for more information.
When towing at high altitude on steep uphill
grades, consider the following: Engine coolant at
higher altitudes will boil at a lower temperature
than at or near sea level. If you turn your engine
off immediately after towing at high altitude on
steep uphill grades, your vehicle may show signs
similar to engine overheating. To avoid this, let
the engine run while parked (preferably on
level ground) with the automatic transmission in
PARK (P) for a few minutes before turning
the engine off. If you do get the overheat warning,
seeEngine Overheating on page 473.
435

A. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 464.
B. Air Filter Restriction Indicator (If Equipped).
SeeEngine Air Cleaner/Filter on page 464.
C. Coolant Surge Tank and Pressure Cap.
SeeCooling System on page 477andCoolant
Surge Tank Pressure Cap on page 473.
D. Remote Positive (+) Terminal. SeeJump
Starting on page 491.
E. Battery. SeeBattery on page 490.
F. Engine Oil Fill Cap. See “When to Add Engine
Oil” underEngine Oil on page 459.
G. Automatic Transmission Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 466.
H. Remote Negative (−) Terminal (Out of View).
SeeJump Starting on page 491.
I. Engine Oil Dipstick (Out of View). See
“Checking Engine Oil” underEngine Oil on
page 459.
J. Engine Cooling Fan. SeeCooling System on
page 477.
K. Power Steering Fluid Reservoir. SeePower
Steering Fluid on page 484.L. Brake Master Cylinder Reservoir. See “Brake
Fluid” underBrakes on page 486.
M. Underhood Fuse Block. SeeUnderhood Fuse
Block on page 567.
N. Windshield Washer Fluid Reservoir. See
“Adding Washer Fluid” underWindshield
Washer Fluid on page 485.
Engine Oil
If the CHECK OIL LEVEL message in the Driver
Information Center (DIC) comes on, check the
engine oil level right away. For more information,
see CHECK OIL LEVEL underDIC Warnings and
Messages on page 270. You should check the
engine oil level regularly; this is an added reminder.
Checking Engine Oil
It is a good idea to check the engine oil every time
you get fuel. In order to get an accurate reading,
the oil must be warm and the vehicle must be
on level ground.
459

Checking Coolant
The coolant surge tank is located in the engine
compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 458for more information on location.
{CAUTION:
Turning the surge tank pressure cap when
the engine and radiator are hot can allow
steam and scalding liquids to blow out
and burn you badly. Never turn the surge
tank pressure cap — even a little — when
the engine and radiator are hot.
The vehicle must be on a level surface. When
your engine is cold, the coolant level should be at
the FULL COLD mark.
Adding Coolant
If you need more coolant, add the proper
DEX-COOL®coolant mixture at the surge tank,
but only when the engine is cool.
{CAUTION:
You can be burned if you spill coolant on
hot engine parts. Coolant contains
ethylene glycol, and it will burn if the
engine parts are hot enough. Do not spill
coolant on a hot engine.
When replacing the pressure cap, make sure it is
hand-tight and fully seated.
472

Cooling System
When you decide it is safe to lift the hood, here is
what you will see:
A. Coolant Surge Tank
B. Coolant Surge Tank Pressure Cap
C. Engine Cooling Fan(s){CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing, and tools
away from any underhood electric fan.
If the coolant inside the coolant surge tank is
boiling, do not do anything else until it cools down.
If possible, the vehicle should be parked on a
level surface. Check the coolant level after
the system cools down. Some amount of coolant
may be lost due to overheating.
5.3L Engine (4.8L and 6.0L Similar)
477

The coolant level should be at or above the FULL
COLD mark. If it is not, you may have a leak at
the pressure cap or in the radiator hoses,
heater hoses, radiator, water pump or somewhere
else in the cooling system.
{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
Do not run the engine if there is a leak. If
you run the engine, it could lose all
coolant. That could cause an engine re,
and you could be burned. Get any leak
xed before you drive the vehicle.
478