service CHEVROLET BLAZER 2023 Repair Manual

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
16401961) - 2023 - CRC - 5/17/22
244 Driving and Operating
The electric trailer brake controller should be
installed by your dealer or a qualified
service center.
Trailer Lamps
Always check all trailer lamps are working at
the beginning of each trip, and periodically
on longer trips.
Turn Signals When Towing a Trailer
When properly connected, the trailer turn
signals will illuminate to indicate the vehicle
is turning, changing lanes, or stopping.
When towing a trailer, the arrows on the
instrument cluster will illuminate even if the
trailer is not properly connected or the bulbs
are burned out.
Tow/Haul Mode
For instructions on how to enter Tow/Haul
Mode, seeDriver Mode Control 0206.
Tow/Haul assists when pulling a heavy
trailer or a large or heavy load. See Driver
Mode Control 0206.
Tow/Haul Mode is designed to be most
effective when the vehicle and trailer
combined weight is at least 75% of the
vehicle's Gross Combined Weight Rating (GCWR). See
“Weight of the Trailer” under
Trailer Towing 0238. Tow/Haul Mode is
most useful when towing a heavy trailer or
carrying a large or heavy load:
.Through rolling terrain.
.In stop-and-go traffic.
.In busy parking lots.
Operating the vehicle in Tow/Haul Mode
when lightly loaded or not towing will not
cause damage; however, it is not
recommended and may result in unpleasant
engine and transmission driving
characteristics and reduced fuel economy.
Trailer Sway Control (TSC)
Vehicles with StabiliTrak/Electronic Stability
Control (ESC) have a Trailer Sway Control
(TSC) feature. Trailer sway is unintended
side-to-side motion of a trailer while towing.
If the vehicle is towing a trailer and the TSC
detects that sway is increasing, the vehicle
brakes are selectively applied at each wheel,
to help reduce excessive trailer sway.
If equipped with the Integrated Trailer Brake
Control (ITBC) system, and the trailer has an
electric brake system, StabiliTrak/ESC may
also apply the trailer brakes.
If TSC is enabled, the Traction Control
System (TCS)/StabiliTrak light will flash on
the instrument cluster. Reduce vehicle speed
by gradually removing your foot from the
accelerator. If trailer sway continues,
StabiliTrak/ESC can reduce engine torque to
help slow the vehicle. TSC will not function
if StabiliTrak/ESC is turned off. See Traction
Control/Electronic Stability Control 0204.
{Warning
Trailer sway can result in a crash and in
serious injury or death, even if the
vehicle is equipped with TSC.
If the trailer begins to sway, reduce
vehicle speed by gradually removing your
foot from the accelerator. Then pull over
to check the trailer and vehicle to help
correct possible causes, including an
improperly or overloaded trailer,
unrestrained cargo, improper trailer hitch
(Continued)

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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Driving and Operating 245
Warning (Continued)
configuration, or improperly inflated or
incorrect vehicle or trailer tires. See
Towing Equipment0241 for trailer
ratings and hitch setup recommendations.
Trailer Tires
Special Trailer (ST) tires differ from vehicle
tires. Trailer tires are designed with stiff
sidewalls to help prevent sway and to
support heavy loads. These features can
make it difficult to determine if the trailer
tire pressures are low only based on a visual
inspection.
Always check all trailer tire pressures before
each trip when the tires are cool. Low trailer
tire pressure is a leading cause of trailer tire
blowouts.
Trailer tires deteriorate over time. The trailer
tire sidewall will show the week and year
the tire was manufactured. Many trailer tire
manufacturers recommend replacing tires
more than six years old. Overloading is another leading cause of
trailer tire blowouts. Never load your trailer
with more weight than the tires are
designed to support. The load rating is on
the trailer tire sidewall.
Always know the maximum speed rating for
the trailer tires before driving. This may be
significantly lower than the vehicle tire
speed rating. The speed rating may be on
the trailer tire sidewall. If the speed rating is
not shown, the default trailer tire speed
rating is 105 km/h (65 mph).
Conversions and Add-Ons
Add-On Electrical Equipment
{Warning
The Data Link Connector (DLC) is used for
vehicle service and Emission Inspection/
Maintenance testing. See
Malfunction
Indicator Lamp (Check Engine Light) 0101.
A device connected to the DLC —such as
an aftermarket fleet or driver-behavior
tracking device —may interfere with
vehicle systems. This could affect vehicle (Continued)
Warning (Continued)
operation and cause a crash. Such devices
may also access information stored in the
vehicle’s systems.
Caution
Some electrical equipment can damage
the vehicle or cause components to not
work and would not be covered by the
vehicle warranty. Always check with your
dealer before adding electrical equipment.
Add-on equipment can drain the vehicle's
12-volt battery, even if the vehicle is not
operating.
The vehicle has an airbag system. Before
attempting to add anything electrical
to the vehicle, see Servicing the
Airbag-Equipped Vehicle 060 and
Adding Equipment to the Airbag-Equipped
Vehicle 061.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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246 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 247
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 247
Accessories and Modifications . . . . . . . . . 247
Vehicle Checks
Doing Your Own Service Work . . . . . . . . 247
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Engine Compartment Overview . . . . . . . . 250
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253
Engine Oil Life System . . . . . . . . . . . . . . . . . 255
Automatic Transmission Fluid . . . . . . . . . . 255
Engine Air Filter Life System . . . . . . . . . . 256
Engine Air Cleaner/Filter . . . . . . . . . . . . . . 256
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 258
Engine Overheating . . . . . . . . . . . . . . . . . . . . 261
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 262
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Battery - North America . . . . . . . . . . . . . . . 264
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . 265
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
Wiper Blade Replacement . . . . . . . . . . . . . 265
Windshield Replacement . . . . . . . . . . . . . . 266
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 267
Bulb Replacement
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
Electrical System
High Voltage Devices and Wiring . . . . . 268
Electrical System Overload . . . . . . . . . . . . 268
Fuses and Circuit Breakers . . . . . . . . . . . . 269
Engine Compartment Fuse Block . . . . . . 270
Instrument Panel Fuse Block . . . . . . . . . . . 273
Rear Compartment Fuse Block . . . . . . . . . 275
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . 277
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
Summer Tires . . . . . . . . . . . . . . . . . . . . . . . . . 278
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 278
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 280
Tire Terminology and Definitions . . . . . . 281
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 284
Tire Pressure Monitor System . . . . . . . . . 285
Tire Pressure Monitor Operation . . . . . . 286
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 289
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 289
When It Is Time for New Tires . . . . . . . . 290
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . 291 Different Size Tires and Wheels . . . . . . . 292
Uniform Tire Quality Grading . . . . . . . . . 292
Wheel Alignment and Tire Balance . . . . 293
Wheel Replacement . . . . . . . . . . . . . . . . . . . 294
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 294
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 295
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . 296
Compact Spare Tire . . . . . . . . . . . . . . . . . . . . 301
Jump Starting
Jump Starting - North America . . . . . . . . 301
Towing the Vehicle
Transporting a Disabled Vehicle . . . . . . . 303
Recreational Vehicle Towing . . . . . . . . . . . 305
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 311
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314

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Vehicle Care 247
General Information
For service and parts needs, visit your
dealer. You will receive genuine GM parts
and GM-trained and supported service
people.
Genuine GM parts have one of these marks:
California Perchlorate Materials
Requirements
Certain types of automotive applications,
such as airbag initiators, seat belt
pretensioners, and lithium batteries
contained in electronic keys, may contain
perchlorate materials. Perchlorate Material–special handling may apply. See
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and Modifications
Adding non-dealer accessories or making
modifications to the vehicle can affect
vehicle performance and safety, including
such things as airbags, braking, stability,
ride and handling, emissions systems,
aerodynamics, durability, Driver Assistance
Systems, and electronic systems like antilock
brakes, traction control, and stability control.
These accessories or modifications could
even cause malfunction or damage not
covered by the vehicle warranty.
Damage to suspension components caused
by modifying vehicle height outside of
factory settings will not be covered by the
vehicle warranty.
Damage to vehicle components resulting
from modifications or the installation or use
of non-GM certified parts, including control
module or software modifications, is not
covered under the terms of the vehicle
warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to complement
and function with other systems on the
vehicle. See your dealer to accessorize the
vehicle using genuine GM Accessories
installed by a dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 061.
Vehicle Checks
Doing Your Own Service Work
{Warning
It can be dangerous to work on your
vehicle if you do not have the proper
knowledge, service manual, tools,
or parts. Always follow owner’s manual
procedures and consult the service
manual for your vehicle before doing any
service work.
If doing some of your own service work, use
the proper service manual. It tells you much
more about how to service the vehicle than
this manual can. To order the proper service
manual, see Publication Ordering
Information 0336.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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248 Vehicle Care
This vehicle has an airbag system. Before
attempting to do your own service work,
seeServicing the Airbag-Equipped Vehicle
0 60.
If equipped with remote vehicle start, open
the hood before performing any service
work to prevent remote starting the vehicle
accidentally. See Remote Vehicle Start 014.
Keep a record with all parts receipts and list
the mileage and the date of any service
work performed. See Maintenance Records
0 324.
Caution
Even small amounts of contamination can
cause damage to vehicle systems. Do not
allow contaminants to contact the fluids,
reservoir caps, or dipsticks.
Hood
{Warning
For vehicles with auto engine stop/start,
turn the vehicle off before opening the
hood. If the vehicle is on, the engine will
start when the hood is opened. You or
others could be injured.
{Warning
Components under the hood can get hot
from running the engine. To help avoid
the risk of burning unprotected skin,
never touch these components until they
have cooled, and always use a glove or
towel to avoid direct skin contact.
Clear any snow from the hood before
driving. To open the hood:
1. Pull the hood release lever with the
i. It is on the lower left side of the
instrument panel.
2. Go to the front of the vehicle and locate the secondary release lever under the
front center of the hood. Push the
secondary hood release lever to the right
to release.

Chevrolet Blazer Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
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254 Vehicle Care
Caution
Do not add too much oil. Oil levels above
or below the acceptable operating range
shown on the dipstick are harmful to the
engine. If the oil level is above the
operating range (i.e., the engine has so
much oil that the oil level gets above the
cross-hatched area that shows the proper
operating range), the engine could be
damaged. Drain the excess oil or limit
driving of the vehicle, and seek a service
professional to remove the excess oil.
See Engine Compartment Overview 0250 for
the location of the engine oil fill cap.
Add enough oil to put the level somewhere
in the proper operating range. Push the
dipstick all the way back in when through.
Selecting the Right Engine Oil
Selecting the right engine oil depends on
both the proper oil specification and
viscosity grade. See Recommended Fluids
and Lubricants 0321. Specification
Use full synthetic engine oils that meet the
dexos1 specification. Engine oils that have
been approved by GM as meeting the
dexos1 specification are marked with the
dexos1 approved logo. See
www.gmdexos.com.
Caution
Failure to use the recommended engine
oil or equivalent can result in engine
damage not covered by the vehicle
warranty.
Viscosity Grade
Use SAE 0W-20 viscosity grade engine oil for
the 2.0L L4 engine.
Use SAE 5W-30 viscosity grade engine oil for
the 3.6L V6 engine. Cold Temperature
Operation: In an area of extreme cold,
where the temperature falls below −29 °C(−20 °F), an SAE 0W-30 oil may be used. An
oil of this viscosity grade will provide easier
cold starting for the engine at extremely
low temperatures.
When selecting an oil of the appropriate
viscosity grade, it is recommended to select
an oil of the correct specification. See
“Specification”
earlier in this section.
Engine Oil Additives/Engine Oil Flushes
Do not add anything to the oil. The
recommended oils meeting the dexos1
specification are all that is needed for good
performance and engine protection.
Engine oil system flushes are not
recommended and could cause engine
damage not covered by the vehicle
warranty.
What to Do with Used Oil
Used engine oil contains certain elements
that can be unhealthy for your skin and
could even cause cancer. Do not let used oil
stay on your skin for very long. Clean your
skin and nails with soap and water, or a
good hand cleaner. Wash or properly
dispose of clothing or rags containing used
engine oil. See the manufacturer's warnings
about the use and disposal of oil products.

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Vehicle Care 255
Used oil can be a threat to the environment.
If you change your own oil, be sure to drain
all the oil from the filter before disposal.
Never dispose of oil by putting it in the
trash or pouring it on the ground, into
sewers, or into streams or bodies of water.
Recycle it by taking it to a place that
collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that
indicates when to change the engine oil and
filter. This is based on a combination of
factors which include engine revolutions,
engine temperature, and miles driven. Based
on driving conditions, the mileage at which
an oil change is indicated can vary
considerably. For the oil life system to work
properly, the system must be reset every
time the oil is changed.
When the system has calculated that oil life
has been diminished, it indicates that an oil
change is necessary. A CHANGE ENGINE OIL
SOON message comes on. Change the oil as
soon as possible within the next 1 000 km
(600 mi). It is possible that, if driving under
the best conditions, the oil life system
might indicate that an oil change is notnecessary for up to a year. The engine oil
and filter must be changed at least once a
year and, at this time, the system must be
reset. Your dealer has trained service people
who will perform this work and reset the
system. It is also important to check the oil
regularly over the course of an oil drain
interval and keep it at the proper level.
If the system is ever reset accidentally, the
oil must be changed at 5 000 km (3,000 mi)
since the last oil change. Remember to reset
the oil life system whenever the oil is
changed.
How to Reset the Engine Oil Life System
Reset the system whenever the engine oil is
changed so that the system can calculate
the next engine oil change. To reset the
system:
1. Display the REMAINING OIL LIFE on the DIC. See Driver Information Center (DIC)
(Uplevel) 0112 orDriver Information
Center (DIC) (Base Level) 0109.
2. Press and hold the thumbwheel on the DIC while the Oil Life display is active.
3. Confirm yes, and the oil life will change to 100%. The oil life system can also be reset as
follows:
1. Place the ignition in Service Mode. See Ignition Positions 0192.
2. Display REMAINING OIL LIFE on the DIC menu. See Driver Information Center
(DIC) (Uplevel) 0112 orDriver
Information Center (DIC) (Base Level)
0 109.
3. Fully press and release the accelerator pedal three times within five seconds.
4. If the display changes to 100%, the system is reset.
If the CHANGE ENGINE OIL SOON message
comes back on when the vehicle is started,
the engine oil life system has not been
reset. Repeat the procedure.
Automatic Transmission Fluid
It is not necessary to check the transmission
fluid level. A transmission fluid leak is the
only reason for fluid loss. If a leak occurs,
take the vehicle to the dealer and have it
repaired as soon as possible.
Change the fluid at the intervals listed in
Maintenance Schedule 0317, and be sure to
use the transmission fluid listed in
Recommended Fluids and Lubricants 0321.

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Vehicle Care 259
Warning (Continued)
engine if there is a leak; all coolant could
leak out. That could cause an engine fire
and can burn you. Fix any leak before
driving the vehicle.
Use a 50/50 mixture of clean, drinkable
water and DEX-COOL coolant. 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.
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, or by 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.
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. See
Engine
Overheating 0261. The coolant surge tank is in the engine
compartment on the driver side of the
vehicle. See
Engine Compartment Overview
0 250.
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.

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Vehicle Care 261
6. Verify coolant level after the engine isshut off and the coolant is cold.
If necessary, repeat coolant fill procedure
Steps 1–6.
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.
2.0L L4 Engine Only - Automatic Coolant
Service Fill Instructions
If equipped, this feature assists in filling and
removing air from the cooling system after
service of components or when coolant is
added after being too low.
To activate the fill and air removal process:
1. With a cold system, add coolant to the indicated mark on the surge tank.
2. Replace the cap on the surge tank.
3. Connect the vehicle to a battery charger.
4. Turn the ignition to Service Mode. See Ignition Positions 0192. 5. Turn off the air conditioning.
6. Set the parking brake.
7. At the same time, press the accelerator
and the brake for two seconds, then
release.
At the end of the cycle, check the coolant
level in the surge tank and add coolant if it
is low. Turn off the vehicle, allow the
Electronic Control Module (ECM) to go to
sleep, about two minutes, and repeat
Steps 4–7.
Listen for pump activation and movement of
the control valves while watching the level
of the coolant in the surge tank. If the tank
empties, turn the ignition off, carefully
remove the surge tank cap, refill to the
indicated mark, and repeat Steps 4–7. The
fill and air removal process will run for
approximately 10 minutes.
Engine Overheating
The vehicle has several indicators to warn of
the engine overheating.
There is an engine coolant temperature
gauge on the instrument cluster. See Engine
Coolant Temperature Gauge 097. The
vehicle may also display a message on the
Driver Information Center (DIC). If the decision is made not to lift the hood
when this warning appears, get service help
right away. See
Roadside Assistance Program
0 332.
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 fan is running. If the engine is
overheating, the fan should be running. If it
is not, do not continue to run the engine.
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
Compartment
{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 (Continued)

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Vehicle Care 263
Caution (Continued)
.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.
{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 0326.
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 Engine
Compartment Overview 0250 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: