2018 CADILLAC ATS check engine

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
VEHICLE CARE 255
damage. In this mode, there is
significant loss in power and engine
performance.
The engine coolant temperature
warning light comes on in the
instrument cluster, to indicate the
vehicle has entered overheated engine
protection operating mode. The
temperature gauge also indicates an
overheat condition exists. Driving
extended distances and/or towing a
trailer in the overheat protection
mode should be avoided.
Power Steering Fluid
(LF3 and LFX with AWD)
The power steering fluid reservoir is
under the engine cover on the
passenger side toward the rear of the
engine compartment. SeeEngine
Compartment Overview 0240.
When to Check Power Steering
Fluid
It is not necessary to regularly check
power steering fluid unless you
suspect there is a leak in the system
or an unusual noise is heard. A fluid
loss in this system could indicate a
problem. Have the system inspected
and repaired.
How to Check Power Steering
Fluid
Check the level when the engine
is cool.
To check the power steering fluid:
1. Remove the engine cover. Refer toEngine Cover 0243.
2. Wipe the cap and the top of the reservoir clean.
3. Turn the cap counterclockwise and pull it straight up.
4. Wipe the dipstick with a clean rag.
5. Replace the cap and completely tighten it. 6. Remove the cap again and look
at the fluid level on the dipstick.
The fluid level should be
between MIN and MAX on the
dipstick.
What to Use
To determine what kind of fluid to
use, see Recommended Fluids and
Lubricants 0332. Always use the
proper fluid.
Power Steering Fluid (LFX
with FWD)
The vehicle has electric power steering
and does not use power steering fluid.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
VEHICLE CARE 257
Caution
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. See Capacities and
Specifications 0337.
Brake pads should be replaced as
complete 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 expected can change in
many other ways if the wrong
replacement brake parts are installed
or if parts are improperly installed.
Brake Fluid
The brake master cylinder reservoir is
filled with GM approved DOT 3 brake
fluid as indicated on the reservoir cap.
See Engine Compartment Overview
0 240 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.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
VEHICLE CARE 259
Warning (Continued)
America0306 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.
All-Wheel Drive
Transfer Case
Under normal driving conditions,
transfer case fluid does not require
maintenance unless there is a fluid
leak or unusual noise. If required,
have the transfer case serviced by
your dealer.
Starter Switch Check
{Warning
When you are doing this inspection,
the vehicle could move suddenly.
If the vehicle moves, you or others
could be injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular brake. See
Electric Parking Brake 0194.
Do not use the accelerator pedal,
and be ready to turn off the
engine immediately if it starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.
Automatic Transmission
Shift Lock Control Function
Check
{Warning
When you are doing this inspection,
the vehicle could move suddenly.
If the vehicle moves, you or others
could be injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Firmly apply the parking brake. See Electric Parking Brake 0194.
Be ready to apply the regular
brake immediately if the vehicle
begins to move.
3. With the engine off, turn the ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
260 VEHICLE CARE
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
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
parking brake.
. To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.
. To check the P (Park) mechanism's
holding ability: With the engine
running, shift to P (Park). Then
release the parking brake followed
by the regular brake.
Contact your dealer if service is
required.
Wiper Blade Replacement
Windshield wiper blades should be
inspected for wear or cracking.
It is a good idea to clean the wiper
blade assembly on a regular basis.
When worn, or when cleaning is
ineffective, replace the wiper blade.
For proper windshield wiper blade
length and type, see Maintenance
Replacement Parts 0333.
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 wiper blade: 1. Pull the wiper assembly away from the windshield.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
VEHICLE CARE 265
Headlamp Wiring
An electrical overload may cause the
lamps to go on and off, or in some
cases to remain off. Have the
headlamp wiring checked right away if
the lamps go on and off or remain off.
Windshield Wipers
If the wiper motor overheats due to
heavy snow or ice, the windshield
wipers will stop until the motor cools
and will then restart.
Although the circuit is protected from
electrical overload, overload due to
heavy snow or ice may cause wiper
linkage damage. Always clear ice and
heavy snow from the windshield
before using the windshield wipers.
If the overload is caused by an
electrical problem and not snow or
ice, be sure to get it fixed.
Fuses and Circuit Breakers
The wiring circuits in the vehicle are
protected from short circuits by a
combination of fuses and circuitbreakers. This greatly reduces the
chance of damage caused by electrical
problems.
{Danger
Fuses and circuit breakers are
marked with their ampere rating.
Do not exceed the
specified amperage rating when
replacing fuses and circuit breakers.
Use of an oversized fuse or circuit
breaker can result in a vehicle fire.
You and others could be seriously
injured or killed.
To check a fuse, look at the
silver-colored band inside the fuse.
If the band is broken or melted,
replace the fuse. Be sure to replace a
bad fuse with a new one of the
identical size and rating.
Fuses of the same amperage can be
temporarily borrowed from another
fuse location, if a fuse goes out.
Replace the fuse as soon as possible.
Engine Compartment Fuse
Block
To remove the fuse block cover,
squeeze the three retaining clips on
the cover and lift it straight up.
Caution
Spilling liquid on any electrical
component on the vehicle may
damage it. Always keep the covers
on any electrical component.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
VEHICLE CARE 307
The vehicle has a battery cover which
must be removed to gain access to the
battery for jump starting.
1. Clips
2. Pivot Points
To remove the battery cover:1. Release the two rear clips (1).
2. Lift the battery cover up toward the front of the vehicle to release
it from the pivot points (2) and
remove.
3. Reverse Steps 1 and 2 to reinstall the battery cover.
The vehicle has a remote positive (+)
terminal under a trim cover. It is
under the battery cover on the driver
side of the engine compartment. See
Engine Compartment Overview 0240.
Always use this remote positive
terminal.The vehicle has a remote negative (−)
ground location. It is located on the
driver side of the engine
compartment. See Engine Compartment
Overview 0240. Always use this
remote ground location, instead of the
terminal on the battery.
These posts are used instead of a
direct connection to the battery.
1. Check the other vehicle. It must have a 12-volt battery with a
negative ground system.

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
322 SERVICE AND MAINTENANCE
Proper vehicle maintenance helps to
keep the vehicle in good working
condition, improves fuel economy, and
reduces vehicle emissions.
Because of the way people use
vehicles, maintenance needs vary.
There may need to be more frequent
checks and services. The Additional
Required Services - Normal are for
vehicles that:
.Carry passengers and cargo within
recommended limits on the Tire
and Loading Information label. See
Vehicle Load Limits 0179.
. Are driven on reasonable road
surfaces within legal driving limits.
. Use the recommended fuel.
See Recommended Fuel (LFX 3.6L
V6 Engine) 0226 orRecommended
Fuel (LF3 3.6L Twin Turbo
V6 Engine) 0226.
Refer to the information in the
Maintenance Schedule Additional
Required Services - Normal chart. The Additional Required Services -
Severe are for vehicles that are:
.
Mainly driven in heavy city traffic
in hot weather
. Mainly driven in hilly or
mountainous terrain
. Frequently towing a trailer
. Used for high speed or competitive
driving
. Used for taxi, police, or delivery
service
Refer to the information in the
Maintenance Schedule Additional
Required Services - Severe chart.
{Warning
Performing maintenance work can
be dangerous and can cause serious
injury. Perform maintenance work
only if the required information,
proper tools, and equipment are
available. If they are not, see your
dealer to have a trained technician
do the work. See Doing Your Own
Service Work 0238.
Maintenance Schedule
Owner Checks and Services
At Each Fuel Stop
.
Check the engine oil level. See
Engine Oil 0244.
Once a Month
. Check the tire inflation pressures.
See Tire Pressure 0279.
. Inspect the tires for wear. See Tire
Inspection 0285.
. Check the windshield washer fluid
level. See Washer Fluid 0256.
Engine Oil Change
When the CHANGE ENGINE OIL
SOON message displays, have the
engine oil and filter changed within
the next 1 000 km/600 mi. If driven
under the best conditions, the engine
oil life system may not indicate the
need for vehicle service for up to a
year. The engine oil and filter must be
changed at least once a year and the
oil life system must be reset. Your
trained dealer technician can perform
this work. If the engine oil life system

Cadillac XTS Owner Manual (GMNA-Localizing-U.S./Canada-12032610) -
2019 - crc - 8/22/18
SERVICE AND MAINTENANCE 323
is reset accidentally, service the
vehicle within 5 000 km/3,000 mi since
the last service. Reset the oil life
system when the oil is changed. See
Engine Oil Life System0246.
Air Conditioning Desiccant
(Replace Every Seven Years)
The air conditioning system requires
maintenance every seven years. This
service requires replacement of the
desiccant to help the longevity and
efficient operation of the air
conditioning system. This service can
be complex. See your dealer.
Tire Rotation and Required
Services Every 12 000 km/
7,500 mi
Rotate the tires, if recommended for
the vehicle, and perform the following
services. See Tire Rotation0285.
. Check engine oil level and oil
life percentage. If needed, change
engine oil and filter, and reset oil
life system.
See Engine Oil 0244 and Engine Oil
Life System 0246. .
Check engine coolant level. See
Cooling System 0250.
. Check windshield washer fluid
level. See Washer Fluid 0256.
. Check tire inflation pressures. See
Tire Pressure 0279.
. Inspect tire wear. See Tire
Inspection 0285.
. Visually check for fluid leaks.
. Inspect engine air cleaner filter.
See Engine Air Cleaner/Filter 0248.
. Inspect brake system. See Exterior
Care 0312.
. Visually inspect steering,
suspension, and chassis
components for damage, including
cracks or tears in the rubber boots,
loose or missing parts, or signs of
wear at least once a year. See
Exterior Care 0312.
. Inspect power steering for proper
attachment, connections, binding,
leaks, cracks, chafing, etc. .
Visually inspect halfshafts and
drive shafts for excessive wear,
lubricant leaks, and/or damage
including: tube dents or cracks,
constant velocity joint or universal
joint looseness, cracked or missing
boots, loose or missing boot
clamps, center bearing excessive
looseness, loose or missing
fasteners, and axle seal leaks.
. Check restraint system
components. See Safety System
Check 075.
. Visually inspect fuel system for
damage or leaks.
. Visually inspect exhaust system
and nearby heat shields for loose
or damaged parts.
. Lubricate body components. See
Exterior Care 0312.
. Check starter switch. See Starter
Switch Check 0259.