
Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
14400528) - 2021 - CRC - 11/7/19
Driving and Operating 231
.Roads with poor lane markings, such as
two-lane roads.
If the LKA system is not functioning
properly when lane markings are clearly
visible, cleaning the windshield may help.
A camera blocked message may display if
the camera is blocked. Some driver
assistance systems may have reduced
performance or not work at all. An LKA or
LDW unavailable message may display if the
systems are temporarily unavailable. This
message could be due to a blocked camera.
The LKA system does not need service. Clean
the outside of the windshield behind the
rearview mirror.
LKA assistance and/or LDW alerts may occur
due to tar marks, shadows, cracks in the
road, temporary or construction lane
markings, or other road imperfections. This
is normal system operation; the vehicle does
not need service. Turn LKA off if these
conditions continue.Fuel
Top Tier Fuel
GM recommends the use of TOP TIER
Detergent Gasoline to keep the engine clean,
reduce engine deposits, and maintain
optimal vehicle performance. Look for the
TOP TIER Logo or see www.toptiergas.com
for a list of TOP TIER Detergent Gasoline
marketers and applicable countries.
Recommended Fuel
Use regular unleaded gasoline meeting
ASTM specification D4814 with a posted
octane rating of 87 —(R+M)/2 —or higher.
Do not use gasoline with a posted octane
rating of less than 87, as this may cause
engine knock and will lower fuel economy.
Do not use any fuel labeled E85 or FlexFuel.
Do not use gasoline with ethanol levels
greater than 15% by volume.
Prohibited Fuels
Caution
Do not use fuels with any of the
following conditions; doing so may
damage the vehicle and void its
warranty:
(Continued)

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232 Driving and Operating
Caution (Continued)
.For vehicles that are not FlexFuel, fuel
labeled greater than 15% ethanol by
volume, such as mid-level ethanol
blends (16–50% ethanol), E85,
or FlexFuel.
.Fuel with any amount of methanol,
methylal, ferrocene, and aniline. These
fuels can corrode metal fuel system
parts or damage plastic and rubber
parts.
.Fuel containing metals such as
methylcyclopentadienyl manganese
tricarbonyl (MMT), which can damage
the emissions control system and
spark plugs.
.Fuel with a posted octane rating of
less than the recommended fuel. Using
this fuel will lower fuel economy and
performance, and may decrease the
life of the emissions catalyst.
Fuels in Foreign Countries
The U.S., Canada, and Mexico post fuel
octane ratings in anti-knock index (AKI). For
fuel not to use in a foreign country, see
Prohibited Fuels0231.
Fuel Additives
TOP TIER Detergent Gasoline is highly
recommended for use with your vehicle.
If your country does not have TOP TIER
Detergent Gasoline, add ACDelco Fuel
System Treatment Plus−Gasoline to the
vehicle’s gasoline fuel tank at every oil
change or 15 000 km (9,000 mi), whichever
occurs first. TOP TIER Detergent Gasoline and
ACDelco Fuel System Treatment Plus
−Gasoline will help keep your vehicle’s
engine fuel deposit free and performing
optimally.
Filling the Tank
An arrow on the fuel gauge indicates which
side of the vehicle the fuel door is on. See
Fuel Gauge 093.
{Warning
Fuel vapors and fuel fires burn violently
and can cause injury or death.
Follow these guidelines to help avoid
injuries to you and others:
.Read and follow all the instructions on
the fuel pump island.
(Continued)
Warning (Continued)
.Turn off the engine when refueling.
.Keep sparks, flames, and smoking
materials away from fuel.
.Do not leave the fuel pump
unattended.
.Avoid using electronic devices while
refueling.
.Do not re-enter the vehicle while
pumping fuel.
.Keep children away from the fuel
pump and never let children
pump fuel.
.Before touching the fill nozzle, touch a
metallic object to discharge static
electricity from your body.
.Fuel can spray out if the fuel cap is
opened too quickly. This spray can
happen if the tank is nearly full, and is
more likely in hot weather. Open the
fuel cap slowly and wait for any hiss
noise to stop, then unscrew the cap all
the way.

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 243
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 244
California Proposition 65 Warning . . . . . 244
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 244
Accessories and Modifications . . . . . . . . . 245
Vehicle Checks
Doing Your Own Service Work . . . . . . . . 245
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 245
Engine Compartment Overview . . . . . . . . 247
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 250
Engine Oil Life System . . . . . . . . . . . . . . . . . 252
Automatic Transmission Fluid . . . . . . . . . . 252
Engine Air Filter Life System . . . . . . . . . . . 253
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . 253
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 255
Engine Overheating . . . . . . . . . . . . . . . . . . . 258
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 259
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260
Battery - North America . . . . . . . . . . . . . . . 261
All-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . . . 263
Starter Switch Check . . . . . . . . . . . . . . . . . . 263
Automatic Transmission Shift Lock Control Function Check . . . . . . . . . . . . . . 263
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 264 Wiper Blade Replacement . . . . . . . . . . . . . 264
Windshield Replacement . . . . . . . . . . . . . . 265
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . 265
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 266
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 266
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 267
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Headlamps, Front Turn Signal,
Sidemarker, and Parking Lamps (Base
Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Headlamps, Front Turn Signal, Sidemarker, and Parking Lamps
(Uplevel) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 268
Fog Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
Taillamps, Turn Signal, Sidemarker, Stoplamps, and Back-Up Lamps (Base
Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 269
Taillamps, Turn Signal, Sidemarker, Stoplamps, and Back-Up Lamps
(Uplevel) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 271
Electrical System
Electrical System Overload . . . . . . . . . . . . . 273
Fuses and Circuit Breakers . . . . . . . . . . . . . 274
Engine Compartment Fuse Block . . . . . . 274
Instrument Panel Fuse Block . . . . . . . . . . . 277
Rear Compartment Fuse Block . . . . . . . . . 278
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . 280
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . . 281
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 282
Tire Terminology and Definitions . . . . . . 283
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 285
Tire Pressure Monitor System . . . . . . . . . 286
Tire Pressure Monitor Operation . . . . . . . 287
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . 290
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 290
When It Is Time for New Tires . . . . . . . . 291
Buying New Tires . . . . . . . . . . . . . . . . . . . . . 292
Different Size Tires and Wheels . . . . . . . 293
Uniform Tire Quality Grading . . . . . . . . . 293
Wheel Alignment and Tire Balance . . . . 295
Wheel Replacement . . . . . . . . . . . . . . . . . . . 295
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 296
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . 297
Compact Spare Tire . . . . . . . . . . . . . . . . . . . . 301
Jump Starting
Jump Starting - North America . . . . . . . . 302
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . . . . . 304
Recreational Vehicle Towing . . . . . . . . . . . 305

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262 Vehicle Care
Warning (Continued)
birth defects or other reproductive harm.
Batteries also contain other chemicals
known to the State of California to cause
cancer.WASH HANDS AFTER HANDLING.
For more information go to
www.P65Warnings.ca.gov/
passenger-vehicle.
See California Proposition 65 Warning 0244
and the back cover.
Vehicle Storage
{Warning
Batteries have acid that can burn you and
gas that can explode. You can be badly
hurt if you are not careful. See Jump
Starting - North America 0302 for tips on
working around a battery without
getting hurt.
Infrequent Usage: Remove the black,
negative (−) cable from the battery to keep
the battery from running down.
Extended Storage: Remove the black,
negative (−) cable from the battery or use a
battery trickle charger.
Negative Battery Cable Disconnection
{Warning
Before disconnecting the negative battery
cable, turn off all features, turn the
ignition off, and remove the key,
if equipped, from the vehicle. If this is
not done, you or others could be injured,
and the vehicle could be damaged.
Caution
If the battery is disconnected with the
ignition on or the vehicle in Retained
Accessory Power (RAP), the OnStar
back-up battery will be permanently
discharged and will need to be replaced.
1. Make sure the lamps, features, and accessories are turned off.
2. Turn the ignition off and remove the key, if equipped.3. Loosen the negative battery cable nut (1).
4. Remove the negative battery cable (2)from the battery.
Negative Battery Cable Reconnection
Caution
When reconnecting the battery:
.Use the original nut from the vehicle
to secure the negative battery cable.
Do not use a different nut. If you
need a replacement nut, see your
dealer.
(Continued)

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 265
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 andpush 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
When a windshield replacement is needed
and the vehicle is equipped with a
front-looking camera sensor for the Driver
Assistance Systems, the windshield must be
installed according to GM specifications for
these systems to work properly. If it is not,
there may be unexpected behavior and/or
messages from these systems.
Gas Strut(s)
This vehicle is equipped with gas strut(s) to
provide assistance in lifting and holding
open the hood/trunk/liftgate system in full
open position.
{Warning
If the gas struts that hold open the hood,
trunk, and/or liftgate fail, you or others
could be seriously injured. Take the
vehicle to your dealer for service
immediately. Visually inspect the gas
struts for signs of wear, cracks, or other
damage periodically. Check to make sure
the hood/trunk/liftgate is held open with
enough force. If struts are failing to hold
the hood/trunk/liftgate, do not operate.
Have the vehicle serviced.
Caution
Do not apply tape or hang any objects
from gas struts. Also do not push down
or pull on gas struts. This may cause
damage to the vehicle.
See Maintenance Schedule 0316.

Chevrolet Trailblazer Owner Manual (GMNA-Localizing-U.S./Canada-
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Vehicle Care 267
Desiccant (If equipped)
This vehicle as equipped with desiccant to
reduce fogging inside the headlamp due to
moisture.
The desiccant is consumable and its
performance may change based on the used
period and environment.
If fogging inside the headlamp due to
moisture continues for a long time, see your
dealer for service.
Halogen Bulbs
{Warning
Halogen bulbs have pressurized gas inside
and can burst if you drop or scratch the
bulb. You or others could be injured. Be
sure to read and follow the instructions
on the bulb package.
LED Lighting
This vehicle has several LED lamps. For
replacement of any LED lighting assembly,
contact your dealer.
Headlamps, Front Turn Signal,
Sidemarker, and Parking Lamps
(Base Level)
Headlamp Assembly
DRL and Parking Lamps
The vehicle has LED DRL and parking lamps
on the headlamp assembly.
Low-beam headlamp, High-beam
headlamp and Front Turn Signal Lamps
Driver Side Shown, Passenger Side Similar
1. Front Turn Signal Lamp
2. High-beam Headlamp
3. Low-beam Headlamp
Low-Beam Headlamp and High-Beam
Headlamp 1. Remove the headlamp bulb access cover.
2. Turn the bulb counterclockwise and pull straight back.
3. Disconnect the wiring harness connector from the bulb.

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Vehicle Care 275
The vehicle may not be equipped with all of
the fuses, relays, and features shown.Micro Fuses Usage
F02 CLSTR Micro Fuses Usage
F03 N/A
F06 OSRVM DEFOG F07 L/GATE RELSE
F08 AHL AFL MTR1
F09 VENT SEAT F10 N/A F11 AHL AFL MTR2
F12 N/A
F14 ISRVM REAR VIEW CAMERA F15 DEFC MDL RUN/CRNK
F16 HDLP LVL F17 N/A-DSL
F18 FTZM
F19 N/A
F20 N/A F22 TRLR ST/TRN LT - TRLR
F24 ESCL F25 ECM TCM RUN/CRNK
F26 FRT/REAR WSW PUMP Micro Fuses Usage
F27 IGN COIL-GAS
ECM PT3-DSL
F28 AERO SH
F29 AHL AFL MDL F31 ECM PT2
F32 ENG COMP2
F33 RVC
F34 FRT FOG LP F35 ENG COMP1
F36 ECM PT1
F38 TRLR PRK LAMP - TRLR
F40 AUX WATER PUMP F41 REAR WPR
F42 HORN
F44 REAR WPR PRK F45 A/C CLTCH
F46 N/A
F47 ECM BATT-GAS
ECM BATT-DSL
F49 HDLP HI LH

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276 Vehicle Care
Micro Fuses UsageF50 N/AF51 HDLP HI RH
F52 NOX SOOT SNSR -DSL
TRLR ST/TRN RT - TRLR
F53 N/A
F54 PEPS
F56 CNSTR VENT SOL-GAS
DEFC MDL-DSL
F57 DEFC MDL
F58 TCM BATT
Spare Fuses Usage SF01 SPARE
SF02 SPARE
SF03 SPARE
SF04 SPARE SF05 SPARE
SF06 SPARE ET Fuses Usage
F48 GLOW PLUG
J-Case Fuses Usage F01 N/A
F05 N/A F13 REAR WNDW DEFOG
F21 E-BOOST PWR1
F23 STRTR PINION
F59 N/A
F62 FUEL HTR DSL
F63 N/A
M-case Fuses Usage F04 FRT WPRF30 STRTR SOL F37 AUX OIL PUMP
F39 N/A
F43 PWR WNDW RT F55 PWR WNDW LT
F60 DEF HTR M-case Fuses Usage
F61 N/A
Mini Relays Usage K03 RUN/CRNK
K04 REAR DEFOG
K06 STRTR PINION
K08 PT RLY
K09 FUEL HTR DSL
HC Micro Relays Usage
K01 N/A
K02 N/A
K05 STRTR SOL
K07 A/C CNTRL K10 N/A
Ultra Micro Relays Usage
K11 N/A