Page 217 of 308
Chevrolet BOLT EV Owner Manual (GMNA-Localizing-U.S./Canada-
16404388) - 2023 - CRC - 3/7/22
216 Vehicle Care
Underhood Compartment Overview
Page 218 of 308

Chevrolet BOLT EV Owner Manual (GMNA-Localizing-U.S./Canada-
16404388) - 2023 - CRC - 3/7/22
Vehicle Care 217
1. Windshield Washer Fluid Reservoir. SeeWasher Fluid 0218.
2. Cabin Heating Coolant Reservoir. See Cooling System 0217.
3. High Voltage Battery Coolant Reservoir. See Cooling System 0217.
4. HPDM (High Power Distribution Module).
5. APM (Accessory Power Module), OBCM (On-Board Charging Module).
6. Brake Fluid Reservoir. See Brake Fluid
0 219.
7. SPIM, APM, and Charger Module Coolant Reservoir. See Cooling System 0217.
8. Battery. See Battery - North America
0 220.
9. Underhood Compartment Fuse Block. Underhood Compartment Fuse Block
0229.
Cooling System
It is not necessary to regularly check coolant
unless a leak is suspected or an unusual
noise is heard. A coolant loss could indicate
a problem. Have it inspected and repaired
by your dealer.
The following explains the cooling systems
and how to check coolant levels.
.High Voltage Battery
.Single Power Inverter Module (SPIM),
Accessory Power Module (APM), and
Charger Module
.Cabin Heating
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
outside the battery on a cradle, heats the
coolant until the correct temperature is
reached.
Single Power Inverter Module (SPIM),
Accessory Power Module (APM), and
Charger Module
The SPIM, APM, and charger module are
cooled using a separate coolant loop. These
modules are kept below a maximum
temperature. If the temperature rises above
this temperature, the electric cooling fan will
turn on to cool the coolant.
Cabin Heating
Cabin heating is maintained by coolant
heated by the Coolant Heater Control
Module (CHCM), separate from the power
electronics and battery coolant loops. This
module heats the coolant based on
temperature inputs from the cabin climate
control systems.
Hybrid Cooling System Pressure Caps
The hybrid cooling system reservoirs have
tamper resistant pressure caps. The coolant
should only be serviced by a qualified
technician.
Checking Coolant
The coolant needs to be replaced at the
appropriate interval. See Maintenance
Schedule 0271.
The coolant reservoirs are in the underhood
compartment. See Underhood Compartment
Overview 0216.
Page 219 of 308

Chevrolet BOLT EV Owner Manual (GMNA-Localizing-U.S./Canada-
16404388) - 2023 - CRC - 3/7/22
218 Vehicle Care
1. Cabin Heating Coolant Reservoir
2. High Voltage Battery Coolant Reservoir
3. SPIM, APM, and Charger ModuleCoolant Reservoir
1. Park on a level surface and turn thevehicle off.
2. After the system has completely cooled, check that the coolant level is at the cold
fill mark on the reservoirs.
3. If the coolant level is not visible or needs to be adjusted within the reservoirs,
contact your dealer.
Washer Fluid
What to Use
When windshield washer fluid is needed, 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
Open the cap with the washer symbol on it.
Add washer fluid until the tank is full. See
Underhood Compartment Overview 0216 for
reservoir location.
Caution
.Do not use washer fluid that contains
any type of water repellent coating.
This can cause the wiper blades to
chatter or skip, and may also clog the
washer nozzle.
(Continued)
Caution (Continued)
.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.
.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.
Page 220 of 308

Chevrolet BOLT EV Owner Manual (GMNA-Localizing-U.S./Canada-
16404388) - 2023 - CRC - 3/7/22
Vehicle Care 219
{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.
Caution
Continuing to drive with worn-out brake
linings could result in costly brake
repairs.
Some driving conditions or climates can
cause a brake squeal when the brakes are
first applied, clearing up following several
applications. 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 linings for wear
and evenly tighten wheel nuts in the proper
sequence to torque specifications. See
Capacities and Specifications 0277.
Brake pads should 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 may be required.
Replacing Brake System Parts
Always replace brake system parts with
new, approved replacement parts. If this is
not done, the brakes may not work
properly. The braking performance can
change in many ways if the wrong brake
parts are installed or if parts are improperly
installed.
Brake Fluid
The brake master cylinder reservoir is filled
with GM approved DOT 4 brake fluid as
indicated on the reservoir cap. See
Underhood Compartment Overview 0216 for
the location of the reservoir. Checking Brake Fluid
With the vehicle in P (Park) on a level
surface, the brake fluid level should be
between the minimum and maximum marks
on the brake fluid reservoir.
There are only two reasons why the brake
fluid level in the reservoir may go down:
.Normal brake lining wear. When new
linings are installed, the fluid level goes
back up.
.A fluid leak in the brake hydraulic system.
Have the brake hydraulic system fixed.
With a leak, the brakes will not
work well.
Always clean the brake fluid reservoir cap
and the area around the cap before
removing it.
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 fluid, as necessary,
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 085.
Page 221 of 308

Chevrolet BOLT EV Owner Manual (GMNA-Localizing-U.S./Canada-
16404388) - 2023 - CRC - 3/7/22
220 Vehicle Care
Brake fluid absorbs water over time which
degrades the effectiveness of the brake fluid.
Replace brake fluid at the specified intervals
to prevent increased stopping distance. See
Maintenance Schedule0271.
What to Add
Use only GM approved DOT 4 brake fluid
from a clean, sealed container. See
Recommended Fluids and Lubricants 0273.
{Warning
The wrong or contaminated brake fluid
could result in damage to the brake
system. This could result in the loss of
braking leading to a possible injury.
Always use the proper GM approved
brake fluid.
Caution
If brake fluid is spilled on the vehicle's
painted surfaces, the paint finish can be
damaged. Immediately wash off any
painted surface.
Battery - North America
This vehicle has a high voltage battery and
a standard 12-volt battery. See your dealer if either the 12-volt or high
voltage battery needs service.
12–Volt Battery
The original equipment battery is
maintenance free. Do not remove the cap
and do not add fluid.
Refer to the replacement number shown on
the original battery label when a new 12-volt
battery is needed. The vehicle has an
Absorbent Glass Mat (AGM) 12-volt battery.
Installation of a standard 12-volt battery will
result in reduced 12-volt battery life.
Some 12-volt chargers have an AGM battery
setting. This setting limits the charge
voltage to 14.8 volts and helps extend the
battery life. If available, use the AGM
setting when charging the battery.
{Warning
WARNING:
Battery posts, terminals and
related accessories can expose you to
chemicals including lead and lead
compounds, which are known to the
State of California to cause cancer and
birth defects or other reproductive harm. (Continued)
Warning (Continued)
Wash hands after handling. For more
information go to
www.P65Warnings.ca.gov.
See California Proposition 65 Warning 01.
High Voltage Battery
Only a trained service technician should
inspect, test, or replace the high voltage
battery. The dealer has information on how
to recycle the high voltage battery.
There is also information available at
https://www.recyclemybattery.com.
{Warning
Damage to the high voltage battery or
high voltage system can create a risk of
electric shock, overheating, or fire.
If the vehicle is damaged from a
moderate to severe crash, flood, fire,
or other event, the vehicle should be
inspected as soon as possible. Until the
vehicle has been inspected, store it
outside at least 15 m (50 ft) from any
(Continued)
Page 222 of 308

Chevrolet BOLT EV Owner Manual (GMNA-Localizing-U.S./Canada-
16404388) - 2023 - CRC - 3/7/22
Vehicle Care 221
Warning (Continued)
structure or anything that can burn.
Ventilate the vehicle by opening a
window or a door.
Contact Customer Assistance as soon as
possible to determine whether an
inspection is needed. SeeCustomer
Assistance Offices 0279.
If the vehicle is in a crash, the sensing
system may shut down the high voltage
system. When this occurs, the high voltage
battery is disconnected and the vehicle will
not start. The SERVICE VEHICLE SOON
message in the Driver Information Center
(DIC) will display. Before the vehicle can
operate again, it must be serviced at your
dealer. If a crash occurs or an airbag(s)
inflates, see “If a Crash Occurs” under
Collision Damage Repair 0283 and
What Will You See after an Airbag Inflates?
0 42 for additional information.
Keep the vehicle plugged in, even when fully
charged, to keep the high voltage battery
temperature ready for the next drive. This is
important when outside temperatures are
extremely hot or cold. Propulsion power may be reduced in
extremely cold temperatures, or if the high
voltage battery is too cold. The message
BATTERY TOO COLD, PLUG IN TO WARM will
display.
A vehicle cover, which can reduce sun
loading on the vehicle and improve high
voltage battery life, is available from your
dealer.
See
Radio Frequency Statement 0286.
Vehicle Storage
The best way to store the vehicle for any
length of time is to plug in the charge cord
and leave it plugged in. The vehicle
monitors and maintains the 12-volt battery
daily. It is okay to leave the vehicle plugged
in for extended periods of time. Once
charged to full, very little energy is required
to maintain the 12-volt battery and high
voltage battery.
If it is not possible to charge the vehicle
with the charge cord left plugged in, be sure
to fully charge the high voltage battery
before storing. The vehicle will stop
maintenance of the 12-volt battery if the
high voltage battery state of charge gets
too low. When storing the vehicle on a long-term
basis:
‐
Keep the high voltage battery state of
charge at 30%.
‐ Attach an AGM/VRLA compatible battery
tender or trickle charger to the 12-volt
battery.
‐ Keep the remote key more than 3 m
(10 ft) away from the vehicle.
12–volt Battery{Warning
Batteries have acid that can burn you and
gas that can explode. You can be badly
hurt if you are not careful. Always wear
eye protection. See Jump Starting - North
America 0256 for tips on working around
a battery without getting hurt.
A trickle charger may be attached to the
12-volt battery terminals or trickle charge
from the underhood remote positive (+) and
negative (–) terminals. See Jump Starting -
North America 0256 for location of these
terminals.
Page 223 of 308

Chevrolet BOLT EV Owner Manual (GMNA-Localizing-U.S./Canada-
16404388) - 2023 - CRC - 3/7/22
222 Vehicle Care
Caution
The vehicle is equipped with an AGM/
VRLA 12-volt battery, which can be
damaged by using the incorrect type of
trickle charger. An AGM/VRLA-compatible
charger must be used, with the
appropriate setting selected. Follow the
trickle charger manufacturer instructions.
With a trickle charger connected to the
12-volt battery, the vehicle will still monitor
the 12-volt battery daily, but it will not use
energy from the high voltage battery for
maintenance.
High Voltage Battery
After extended storage, it is possible that
the vehicle may not operate. If this happens,
the high voltage battery may need to be
plugged in and charged.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check, the
vehicle could begin to move. You or
others could be injured and property
could be damaged. Make sure there is
room in front of the vehicle in case it
begins to roll. Be ready to apply the
regular brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the vehicle
facing downhill. Keeping your foot on the
regular brake, set the Electric Parking
Brake (EPB).
.To check the EPB's holding ability: With
the propulsion system active and the
electric drive unit in N (Neutral), slowly
remove foot pressure from the regular
brake pedal. Do this until the vehicle is
held by the EPB only.
.To check the P (Park) mechanism's holding
ability: With the propulsion system
active, shift to P (Park). Then release the
EPB and slowly remove foot pressure
from the regular brake pedal. Contact your dealer if service is required.
Wiper Blade Replacement
Front Wiper Blade Replacement
Windshield wiper blades should be replaced
periodically. See the
Maintenance Schedule
0 271.
Replacement blades come in different types
and are removed in different ways. For
proper type and length, see Maintenance
Replacement Parts 0274.
Caution
Allowing the wiper arm to touch the
windshield when no wiper blade is
installed could damage the windshield.
Any damage that occurs would not be
covered by the vehicle warranty. Do not
allow the wiper arm to touch the
windshield.
To replace the windshield wiper blade: 1. Pull the windshield wiper assembly away from the windshield.
Page 224 of 308

Chevrolet BOLT EV Owner Manual (GMNA-Localizing-U.S./Canada-
16404388) - 2023 - CRC - 3/7/22
Vehicle Care 223
2. Press the button in the middle of thewiper arm connector, and pull the wiper
blade away from the arm connector.
3. Remove the wiper blade.
4. Reverse Steps 1–3 for wiper blade replacement.
Rear Wiper Blade Replacement
The rear wiper blade and wiper arm have a
cover for protection. The cover must be
removed before the wiper blade can be
replaced. To remove the cover:
1. Slide a plastic tool under the cover and
push upward to unsnap.
2. Slide the cover toward the wiper blade tip to unhook it from the blade
assembly.
3. Remove the cover.
4. After wiper blade replacement, ensure that the cover hook slides into the slot
in the blade assembly.
5. Snap the cover down to secure.
To replace the wiper blade: 1. Lift the wiper arm away from the windshield.
2. Push the release lever (2) to disengagethe hook and push the wiper arm (1) out
of the blade assembly (3).
3. Push the new blade assembly securely on the wiper arm until the release lever
clicks into place.
4. Replace the wiper cover.
Windshield Replacement
Driver Assistance Systems
If the windshield needs to be replaced and
the vehicle is equipped with a front camera
sensor for the Driver Assistance Systems, a
GM replacement windshield is
recommended. The replacement windshield
must be installed according to GM
specifications for proper alignment. If it is
not, these systems may not work properly,