2021 CHEVROLET CORVETTE cooling

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14622938) - 2021 - CRC - 2/10/21
246 Vehicle Care
Warning (Continued)
the wrong mixture, the engine could get
too hot but there would not be an
overheat warning. The engine could catch
fire and you or others could be burned.
Use a mixture of 40% DEX-COOL coolant and
60% clean, drinkable water. If using this
mixture, nothing else needs to be added.
This mixture:
.Gives freezing protection down to −28 °C
(−18 °F), outside temperature.
.Gives boiling protection up to 129 °C
(265 °F), engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
Caution
Do not use anything other than a mix of
DEX-COOL coolant that meets GM
Standard GMW3420 and clean, drinkable
water. Anything else can cause damage
to the engine cooling system and the
vehicle, which would not be covered by
the vehicle warranty. Never dispose of engine coolant by putting
it in the trash, pouring it on the ground,
or into sewers, streams, or bodies of water.
Have the coolant changed by an authorized
service center, familiar with legal
requirements regarding used coolant
disposal. This will help protect the
environment and your health.
If ambient temperatures are anticipated
below
−28 °C (−18 °F), make sure a proper
mixture ratio of 50% DEX-COOL coolant and
50% clean, drinkable water is used.
Checking Coolant
Be sure the cooling system is cool and that
the vehicle is on a level surface.
Check to see if coolant is visible in the
coolant surge tank. If the coolant inside the
coolant surge tank is boiling, do not do
anything else until it cools down. If coolant
is visible but the coolant level is not at or
above the cold fill line, add a mixture of
40% DEX-COOL coolant and 60% clean,
drinkable water at the coolant recovery
tank, but be sure the cooling system is cool
before this is done. See Engine Overheating
0 248. The surge tank is in the engine
compartment. See
Engine Compartment
Overview 0235.
When the engine is cold, the coolant level
should be at the COLD FILL indicator in the
coolant surge tank.
When the engine is hot, the level could be
higher than the COLD FILL indicator. If the
coolant is below the COLD FILL indicator
when the engine is hot, there could be a
leak in the cooling system.
If the coolant is low, add the coolant or take
the vehicle to your dealer for service.

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 247
How to Add Coolant to the Coolant
Surge Tank
{Warning
Spilling coolant on hot engine parts can
burn you. Coolant contains ethylene
glycol and it will burn if the engine parts
are hot enough.
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If coolant is needed, be sure the cooling
system is cool, then add the proper
DEX-COOL coolant mixture directly to the
surge tank. 1. Open the Hatch/Trunk. See Hatch (Trunk)
0 19.
2. When the cooling system, including the
coolant surge tank pressure cap and
engine, is no longer hot, remove the
pressure cap.
Turn the pressure cap slowly
counterclockwise about one-quarter turn
and then stop.
If a hiss is heard, wait for that to stop.
A hiss means there is still some
pressure left.
3. Keep turning the pressure cap slowly, and remove it.
4. Fill the coolant surge tank with theproper mixture until the level inside
stabilizes at the COLD FILL indicator in
the surge tank.
5. With the coolant surge tank pressure cap off, start the engine and let it run until
the engine is hot.
By this time, the coolant level inside the
coolant surge tank may be lower. If the
level is lower, add more of the proper
mixture to the coolant surge tank until
the level stabilizes at the COLD FILL
indicator in the coolant surge tank.
6. Replace the pressure cap tightly.

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14622938) - 2021 - CRC - 2/10/21
248 Vehicle Care
7. Verify coolant level after the engine isshut off and the coolant is cold.
If necessary, repeat coolant fill procedure
Steps 3−7.
If the coolant still is not at the proper
level when the system cools down again,
see your dealer.
Caution
If the pressure cap is not tightly installed,
coolant loss and engine damage may
occur. Be sure the cap is properly and
tightly secured.
Engine Overheating
The vehicle has several indicators to warn of
engine overheating.
There is an engine coolant temperature
gauge on the instrument cluster. See Engine
Coolant Temperature Gauge 084. The
vehicle may also display a message on the
Driver Information Center (DIC).
If the decision is made not to lift the hatch
but to get service help right away, see
Roadside Assistance Program 0311.
If the decision is made to lift the hatch,
make sure the vehicle is parked on a level
surface. Then check to see if the engine cooling fans
are running. There are two cooling fans
located in the front (one at each corner) and
two cooling fans in the rear (one on each
side of the engine). If the engine is
overheating, the fans should be running.
If they are not, do not continue to run the
engine, and have the vehicle serviced.
Caution
Do not run the engine if there is a leak
in the engine cooling system. This can
cause a loss of all coolant and can
damage the system and vehicle. Have
any leaks fixed right away.
If Steam Is Coming from the Engine
{Warning
Steam and scalding liquids from a hot
cooling system are under pressure.
Turning the pressure cap, even a little,
can cause them to come out at high
speed and you could be burned. Never
turn the cap when the cooling system,
including the pressure cap, is hot. Wait
for the cooling system and pressure cap
to cool.
If Steam Is Coming from the Engine
Compartment with no Overheat Warning
Water from rain and car washes could enter
the engine compartment and contact hot
surfaces. If steam is coming from the engine
compartment with no accompanying
overheat warning, no service is needed.
If No Steam Is Coming from the Engine
If an engine overheat warning is displayed
but no steam can be seen or heard, the
problem may not be too serious. Sometimes
the engine can get a little too hot when the
vehicle:
.Climbs a long hill on a hot day.
.Stops after high-speed driving.
.Idles for long periods in traffic.
If the overheat warning is displayed with no
sign of steam: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the highest fan
speed. Open the windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or N (Neutral), and
let the engine idle.

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 249
If the engine coolant temperature gauge is
no longer in the shaded area or an overheat
warning no longer displays, the vehicle can
be driven. Continue to drive the vehicle
slowly for about 10 minutes. Keep a safe
vehicle distance from the vehicle in front.
If the warning does not come back on,
continue to drive normally and have the
cooling system checked for proper fill and
function.
If the warning continues, pull over safely,
and park the vehicle right away.
If there is no sign of steam, idle the engine
for three minutes while parked. If the
warning is still displayed, turn off the
engine until it cools down.
Washer Fluid
What to Use
When the vehicle needs windshield washer
fluid, be sure to read the manufacturer
instructions before use. If the vehicle will be
operating in an area where the temperature
may fall below freezing, use a fluid that has
sufficient protection against freezing.
Adding Washer Fluid
1. Open the hood. SeeHood017.
2. Open the cap with the washer symbol
on it. Add washer fluid until the tank
is full.
Caution
.Do not use washer fluid that contains
any type of water repellent coating.
This can cause the wiper blades to
chatter or skip.
.Do not use engine coolant (antifreeze)
in the windshield washer. It can
damage the windshield washer system
and paint.
.Do not mix water with ready-to-use
washer fluid. Water can cause the
solution to freeze and damage the
washer fluid tank and other parts of
the washer system.
.When using concentrated washer fluid,
follow the manufacturer instructions
for adding water.
(Continued)
Caution (Continued)
.Fill the washer fluid tank only
three-quarters full when it is very cold.
This allows for fluid expansion if
freezing occurs, which could damage
the tank if it is completely full.
Brakes
Disc brake linings have built-in wear
indicators that make a high-pitched warning
sound when the brake linings are worn and
new linings are needed. The sound can come
and go or can be heard all the time when
the vehicle is moving, except when applying
the brake pedal firmly.
{Warning
The brake wear warning sound means
that soon the brakes will not work well.
That could lead to a crash. When the
brake wear warning sound is heard, have
the vehicle serviced.

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 257
The vehicle may not be equipped with all of
the fuses and relays shown.Fuses Usage
F1 –
F2 Front wiper
F3 Cooling fan 1
F4 –
F5 Cooling fan 2
F6 Front blower Fuses Usage
F7 Automatic level control
F8 Shifter interface board module
F9 –
F10 Display IP cluster/HVAC/ Center stack module
F11 USB
F12 – Fuses Usage
F13 –
F14 Glove box F15 –
F16 –
F17 Remote function actuator
F18 Front trunk release
F19 Intelligent battery sensor
F20 Exterior lighting module 1 F21 Exterior lighting module 3
F22 Exterior lighting module 4
F23 Body control module 2
F24 Exterior lighting module 6 F25 Amplifier
F26 Automatic occupant sensing/Electric park
brake
F27 Video processing module
F28 Right headlamp
F29 –

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14622938) - 2021 - CRC - 2/10/21
260 Vehicle Care
FusesUsage
10 Engine control module/ Air conditioning
11 –
12 Lithium ion battery module
13 Active fuel management
14 Seat fan 15 –
16 Exterior lighting module 17 Instrument panel cluster/Shifter interface
board/Transmission
control module/
Electronic brake control
module
18 Engine control module
19 –
20 Sensing and diagnostic module/Inside rear view
mirror
21 Exhaust valve solenoid
22 Fuel pump/Fuel tank zone module Fuses
Usage
23 Tonneau left
24 Tonneau right 25 Convertible top right
26 Convertible top left 27 Electronic suspension control
28 –
29 CGM
30 O2 sensor 31 O2 sensor/Engine oil/ Canister purge/Active
fuel management
32 Ignition even
33 Ignition odd
34 Engine control module 1 35 Engine control module/ Mass air flow Sensor/
O2 sensor/Air
conditioning
36 –
37 Canister vent
38 Latch control module Fuses
Usage
39 Right window switch/ Door lock
40 Left window switch/ Door lock
41 –
42 Engine control module 2
43 –
44 Air conditioning clutch 45 –
46 –
47 –
48 –
49 Auxiliary cooling fan right
50 –
51 –
52 –
53 Starter solenoid
54 Auxiliary cooling fan left

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 277
Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider an
alignment check if there is unusual tire wear
or the vehicle is significantly pulling to one
side or the other. Some slight pull to the
left or right, depending on the crown of the
road and/or other road surface variations
such as troughs or ruts, is normal. If the
vehicle is vibrating when driving on a
smooth road, the tires and wheels may
need to be rebalanced. See your dealer for
proper diagnosis.
Road Imperfections/Crown Effects
The vehicle's precise steering and handling
make it very responsive to road surface
feedback. A slight pull may be felt in the
steering depending on the crown of the
road and/or other road surface variations
such as troughs or ruts. This is normal and
the vehicle does not require service.Tire Chatter/Hop
When driving at slow speeds and in very
tight turns, the vehicle may have tire
chatter/hop. This is normal and the vehicle
does not require service.
Wheel Replacement
Replace any wheel that is bent, cracked,
or badly rusted or corroded. If wheel nuts
keep coming loose, the wheel, wheel bolts,
and wheel nuts should be replaced. If the
wheel leaks air, replace it. Some aluminum
wheels can be repaired. See your dealer if
any of these conditions exist.
Your dealer will know the kind of wheel that
is needed.
Each new wheel should have the same
load-carrying capacity, diameter, width,
offset, and be mounted the same way as
the one it replaces.
Replace wheels, wheel bolts, wheel nuts,
or Tire Pressure Monitor System (TPMS)
sensors with new GM original equipment
parts.
{Warning
Using the wrong replacement wheels,
wheel bolts, or wheel nuts can be
dangerous. It could affect the braking and
handling of the vehicle. Tires can lose air
and cause loss of control, resulting in a
crash. Always use the correct wheel,
wheel bolts, and wheel nuts for
replacement.
Caution
The wrong wheel can also cause
problems with bearing life, brake cooling,
speedometer or odometer calibration,
headlamp aim, bumper height, vehicle
ground clearance, and tire or tire chain
clearance to the body and chassis.
Used Replacement Wheels
{Warning
Replacing a wheel with a used one is
dangerous. How it has been used or how
far it has been driven may be unknown.
(Continued)

Chevrolet Corvette Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Vehicle Care 287
Wheels and Wheel Trim
Use a soft, clean cloth with mild soap and
water to clean the wheels. After rinsing
thoroughly with clean water, dry with a
soft, clean towel. A wax may then be
applied.
Caution
Chrome wheels and chrome wheel trim
may be damaged if the vehicle is not
washed after driving on roads that have
been sprayed with magnesium chloride or
calcium chloride. These are used on roads
for conditions such as dust and ice.
Always wash the chrome with soap and
water after exposure.
Caution
To avoid surface damage on wheels and
wheel trim, do not use strong soaps,
chemicals, abrasive polishes, cleaners,
or brushes. Use only GM approved
cleaners. Do not drive the vehicle through
an automatic car wash that uses silicon
carbide tire/wheel cleaning brushes.
(Continued)
Caution (Continued)
Damage could occur and the repairs
would not be covered by the vehicle
warranty.
Brake System
Visually inspect brake lines and hoses for
proper hook-up, binding, leaks, cracks,
chafing, etc. Inspect disc brake pads for wear
and rotors for surface condition. Inspect
drum brake linings/shoes for wear or cracks.
Inspect other brake parts, including drums,
wheel cylinders, calipers, parking brake,
master cylinder, brake fluid reservoir,
vacuum pipes, electric vacuum pump
including bracket and vent hose, if equipped.
If equipped with Z51, inspect brake cooling
components. SeeTrack Events and
Competitive Driving (Z51 Only) 0180.
Steering, Suspension, and Chassis
Components
Visually inspect steering, suspension, and
chassis components for damaged, loose,
or missing parts or signs of wear at least
once a year. Inspect power steering for proper hook-up,
binding, leaks, cracks, chafing, etc.
Visually check constant velocity joint boots
and axle seals for leaks.
Body Component Lubrication
Lubricate all key lock cylinders, hood hinges,
and liftgate hinges, unless the components
are plastic. Applying silicone grease on
weatherstrips with a clean cloth will make
them last longer, seal better, and not stick
or squeak.
Underbody Maintenance
At least twice a year, spring and fall, use
plain water to flush any corrosive materials
from the underbody. Take care to
thoroughly clean any areas where mud and
other debris can collect.
Do not directly power wash the transfer
case and/or front/rear axle output seals.
High pressure water can overcome the seals
and contaminate the fluid. Contaminated
fluid will decrease the life of the transfer
case and/or axles and should be replaced.