Page 385 of 516

Black plate (19,1)Chevrolet Volt Owner Manual - 2011
Vehicle Care 10-19
Cooling System
(High Voltage Battery)
During vehicle operation and
also during charging, the high
voltage battery cells in the
vehicle are kept within a normal
operating temperature range.
If the temperature rises above this
temperature, the battery cooling
system turns on the air conditioning
compressor and cools the coolant
until the correct temperature is
reached. If the temperature falls
below this temperature, a high
voltage heater, located in the
battery, heats the coolant until the
correct temperature is reached.
What to Use
The high voltage battery coolant
reservoir in the vehicle is filled
with a 50/50 mixture of DEX-COOL
engine coolant and deionized water.
If using this mixture, nothing else
needs to be added.
Checking Coolant
The vehicle must be on a level
surface when checking the coolant
level.
The high voltage battery
coolant reservoir is located
on the passenger side of the
engine compartment. SeeEngine
Compartment Overview on
page 10‑10 for more information
on location.Check to see if coolant is visible
in the high voltage battery coolant
reservoir. If coolant is visible but the
coolant level is below the cold fill
line, there could be a leak in the
cooling system.
The high voltage battery coolant
should only be serviced by a
qualified technician.
Page 386 of 516

Black plate (20,1)Chevrolet Volt Owner Manual - 2011
10-20 Vehicle Care
Cooling System
(Power Electronics and
Charger Modules)
The power electronics and charger
modules are cooled using the same
coolant loop.
The power electronics and charger
modules in the vehicle are kept
below a maximum temperature.
If the temperature rises above
this temperature, the electric
engine cooling fans will turn
on and cool the coolant until the
correct temperature is reached.
What to Use
The power electronics and charger
modules coolant reservoir in the
vehicle is filled with a 50/50 mixture
of DEX-COOL engine coolant
and deionized water. If using this
mixture, nothing else needs to
be added.
Checking Coolant
The vehicle must be on a level
surface when checking the coolant
level.
The power electronics and
charger modules coolant reservoir
is located on the driver side of the
engine compartment. SeeEngine
Compartment Overview on
page 10‑10 for more information
on location.
Check to see if coolant is visible in
the power electronics and charger
modules coolant reservoir. If coolant
is visible but the coolant level is
below the cold fill line, there could
be a leak in the cooling system.
The power electronics and charger
modules coolant should only be
serviced by a qualified technician.
Page 387 of 516

Black plate (21,1)Chevrolet Volt Owner Manual - 2011
Vehicle Care 10-21
Engine Coolant
The engine cooling system in the
vehicle is filled with DEX-COOL
engine coolant. This coolant is
designed to remain in the vehicle for
5 years or 240 000 km (150,000 mi),
whichever occurs first.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
seeEngine Overheating on
page 10‑23.
What to Use
{WARNING
Adding only plain water or some
other liquid to the cooling system
can be dangerous. Plain water
and other liquids, can boil before
the proper coolant mixture will.
The coolant warning system is
set for the proper coolant mixture.
(Continued)
WARNING (Continued)
With plain water or the wrong
mixture, the engine could get too
hot but you would not get the
overheat warning. The engine
could catch fire and you or
others could be burned. Use a
50/50 mixture of clean, drinkable
water and DEX-COOL coolant.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. If using this mixture,
nothing else needs to be added.
This mixture:
.Gives freezing protection down
to −37°C (−34°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.
Notice: If an improper coolant
mixture is used, the engine could
overheat and be badly damaged.
The repair cost would not be
covered by the vehicle warranty.
Too much water in the mixture
can freeze and crack the engine,
radiator, heater core, and other
parts.
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.
Page 388 of 516

Black plate (22,1)Chevrolet Volt Owner Manual - 2011
10-22 Vehicle Care
Checking Coolant
The vehicle must be on a level
surface when checking the coolant
level.
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 mark, add
a 50/50 mixture of clean, drinkable
water and DEX-COOL coolant at the
coolant surge tank, but be sure the
cooling system is cool before this is
done. SeeEngine Overheating on
page 10‑23 for more information.
The coolant reservoir is located
on the passenger side of the
engine compartment. See Engine
Compartment Overview on
page 10‑10 for more information
on location. The coolant level should be at
or above the cold fill line on the
coolant surge tank. If it is not,
there could be a leak in the
cooling system.
How to Add Coolant to the
Coolant Surge Tank
{WARNING
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.
Notice: This vehicle has a
specific coolant fill procedure.
Failure to follow this procedure
could cause the engine to
overheat and be severely
damaged.
{WARNING
The electric cooling fans under
the hood can start up even when
the engine is not running and
can cause injury. Keep hands,
clothing, and tools away from
any underhood electric fan.
{WARNING
Steam and scalding liquids from a
hot cooling system can blow out
and burn you badly. They are
under pressure, and if you
turn the surge tank pressure
cap —even a little —they can
come out at high speed. Never
turn the cap when the cooling
system, including the surge tank
pressure cap, is hot. Wait for the
cooling system and surge tank
pressure cap to cool if you ever
have to turn the pressure cap.
Page 389 of 516

Black plate (23,1)Chevrolet Volt Owner Manual - 2011
Vehicle Care 10-23
If coolant is needed, add the proper
DEX-COOL coolant mixture at the
coolant surge tank.
The coolant surge tank pressure
cap can be removed when the
cooling system, including the
surge tank pressure cap and upper
radiator hose, is no longer hot.
1. Turn the pressure cap slowlycounterclockwise. If a hiss is
heard, wait for that to stop.
A hiss means there is still
some pressure left.
2. Keep turning the cap and remove it.
3. Fill the coolant surge tank with
the proper mixture to the cold
fill line.
4. Replace the pressure cap. Be sure the pressure cap is
hand‐tight and fully seated.
Notice: If the pressure cap is
not tightly installed, coolant loss
and possible engine damage may
occur. Be sure the cap is properly
and tightly secured.
Engine Overheating
The vehicle has an indicator to warn
of engine overheating.
If the decision is made not to
lift the hood when this warning
appears, get service help right
away. See Roadside Assistance
Program on page 13‑6.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Then check to see if the engine
cooling fans are running. If the
engine is overheating, the fans
should be running. If they are not,
do not continue to run the vehicle
and have the vehicle serviced.
Notice: Engine damage from
running the engine without
coolant is not covered by the
warranty.
Page 390 of 516

Black plate (24,1)Chevrolet Volt Owner Manual - 2011
10-24 Vehicle Care
Power Steering Fluid
The vehicle is equipped with an
electric power steering system.
No fluid or general maintenance
is required.
Washer Fluid
What to Use
When adding windshield washer
fluid to the vehicle, be sure to read
the manufacturer's instructions
before use. If operating the vehicle
in an area where the temperature
may fall below freezing, use a fluid
that has sufficient protection against
freezing.
Adding Washer Fluid
The WASHER FLUID LOW ADD
FLUID message will appear on
the Driver Information Center
(DIC) when the fluid level is low.
SeeDriver Information Center (DIC)
on page 5‑43 for more information.
Open the cap with the washer
symbol on it. Add washer fluid
until the tank is full. See Engine
Compartment Overview on
page 10‑10 for reservoir location. Notice
.When using concentrated
washer fluid, follow the
manufacturer's instructions
for adding water.
.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.
Also, water does not clean
as well as washer fluid.
.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.
.Do not use engine coolant
(antifreeze) in the windshield
washer. It can damage the
windshield washer system
and paint.
Page 391 of 516

Black plate (25,1)Chevrolet Volt Owner Manual - 2011
Vehicle Care 10-25
Brakes
This vehicle has disc brakes.
Disc brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or be
heard all the time 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.
Notice: Continuing to drive with
worn-out brake pads could result
in costly brake repair. Some driving conditions or climates
can cause a brake squeal when
the brakes are first applied or
lightly applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in
the proper sequence to torque
specifications in
Capacities and
Specifications on page 12‑2.
Brake linings should always be
replaced as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase
in pedal travel. This could be
a sign that brake service might
be required.
Brake Adjustment
Every time the brakes are applied,
with or without the vehicle moving,
the brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is
complex. Its many parts have to be
of top quality and work well together
if the vehicle is to have really good
braking. The vehicle was designed
and tested with top-quality brake
parts. When parts of the braking
system are replaced, be sure to get
new, approved replacement parts.
If this is not done, the brakes might
not work properly. For example,
installing disc brake pads that are
wrong for the vehicle, can change
the balance between the front
and rear brakes —for the worse.
The braking performance expected
can change in many other ways if
the wrong replacement brake parts
are installed.
Page 392 of 516

Black plate (26,1)Chevrolet Volt Owner Manual - 2011
10-26 Vehicle Care
Brake Fluid
The brake master cylinder reservoir
is filled with DOT 3 brake fluid as
indicated on the reservoir cap.
SeeEngine Compartment Overview
on page 10‑10 for the location of the
reservoir. There are only two reasons why
the brake fluid level in the reservoir
might go down:
.The brake fluid level goes down
because of normal brake lining
wear. When new linings are
installed, the fluid level goes
back up.
.A fluid leak in the brake
hydraulic system can also
cause a low fluid level. Have
the brake hydraulic system fixed,
since a leak means that sooner
or later the brakes will not
work well.
Do not top off the brake fluid.
Adding fluid does not correct a
leak. If fluid is added when the
linings are worn, there will be too
much fluid when new brake linings
are installed. Add or remove brake
fluid, as necessary, only when work
is done on the brake hydraulic
system.
{WARNING
If too much brake fluid is added,
it can spill on the engine
and burn, if the engine is hot
enough. You or others could be
burned, and the vehicle could be
damaged. Add brake fluid only
when work is done on the brake
hydraulic system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light on page 5‑24.