check oil CADILLAC CT6 2018 1.G Owners Manual

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
118 INSTRUMENTS AND CONTROLS
Instruments and
Controls
Controls
Steering Wheel Adjustment . . . . . 119
Steering Wheel Controls . . . . . . . . . 119
Heated Steering Wheel . . . . . . . . . . 119
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Windshield Wiper/Washer . . . . . . . 120
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Power Outlets . . . . . . . . . . . . . . . . . . . . . 123
Wireless Charging . . . . . . . . . . . . . . . . 124
Cigarette Lighter . . . . . . . . . . . . . . . . . . 125
Ashtrays . . . . . . . . . . . . . . . . . . . . . . . . . . 126
Warning Lights, Gauges, and
Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . . . . . 126
Instrument Cluster (Base
Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Instrument Cluster (Uplevel) . . . . 130
Speedometer . . . . . . . . . . . . . . . . . . . . . . 134
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . 134
Trip Odometer . . . . . . . . . . . . . . . . . . . . 134
Tachometer . . . . . . . . . . . . . . . . . . . . . . . 134
Battery Gauge (High Voltage) . . . 135
Fuel Gauge . . . . . . . . . . . . . . . . . . . . . . . . 135 Power Indicator Gauge
(PLUG-IN Only) . . . . . . . . . . . . . . . . . 136
Boost Gauge (Performance Configuration Only) . . . . . . . . . . . . 136
Engine Oil Pressure Gauge (Base
Level Cluster Only) . . . . . . . . . . . . . 137
Engine Oil Temperature Gauge (Performance
Configuration Only) . . . . . . . . . . . . 138
Engine Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . 139
Voltmeter Gauge (Base Level Cluster Only) . . . . . . . . . . . . . . . . . . . . 140
Seat Belt Reminders . . . . . . . . . . . . . . 140
Airbag Readiness Light . . . . . . . . . . 141
Passenger Airbag Status Indicator . . . . . . . . . . . . . . . . . . . . . . . . . 141
Charging System Light . . . . . . . . . . . 142
Malfunction Indicator Lamp (Check Engine Light) . . . . . . . . . . . 143
Service Vehicle Soon Light (PLUG-IN Only) . . . . . . . . . . . . . . . . . 145
Brake System Warning Light . . . . 145
Electric Parking Brake Light . . . . . 145
Service Electric Parking Brake Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . . . . 146
Sport Mode Light . . . . . . . . . . . . . . . . . 146
Winter Driving Mode Light . . . . . . 146 Automatic Vehicle Hold (AVH)
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
Lane Keep Assist (LKA) Light . . . 147
Vehicle Ahead Indicator . . . . . . . . . 147
Pedestrian Ahead Indicator . . . . . . 147
Traction Off Light . . . . . . . . . . . . . . . . 148
StabiliTrak OFF Light . . . . . . . . . . . . 148
Traction Control System (TCS)/ StabiliTrak Light . . . . . . . . . . . . . . . . 148
Engine Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . 149
Tire Pressure Light . . . . . . . . . . . . . . . 149
Engine Oil Pressure Light . . . . . . . . 149
Low Fuel Warning Light . . . . . . . . . 150
Auto Stop Mode (Uplevel Cluster) . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Security Light . . . . . . . . . . . . . . . . . . . . . 150
Vehicle Ready Light (PLUG-IN Only) . . . . . . . . . . . . . . . . . 151
High-Beam On Light . . . . . . . . . . . . . 151
Lamps On Reminder . . . . . . . . . . . . . 151
Cruise Control Light . . . . . . . . . . . . . . 151
Door Ajar Light . . . . . . . . . . . . . . . . . . . 152
Information Displays
Power Flows (PLUG-IN Only) . . . . 152
Programmable Charging (PLUG-IN Only) . . . . . . . . . . . . . . . . . 152
Energy Information (PLUG-IN Only) . . . . . . . . . . . . . . . . . 161

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
138 INSTRUMENTS AND CONTROLS
the normal operating range, check the
vehicle's oil as soon as possible. See
Engine Oil0307.
Caution
Lack of proper engine oil
maintenance can damage the
engine. Driving with the engine oil
low can also damage the engine.
The repairs would not be covered
by the vehicle warranty. Check the
oil level as soon as possible. Add oil
if required, but if the oil level is
within the operating range and the
oil pressure is still low, have the
vehicle serviced. Always follow the
maintenance schedule for changing
engine oil.
Engine Oil Temperature
Gauge (Performance
Configuration Only)
Metric
English
This gauge shows the engine oil
temperature.
If the gauge pointer moves into the
high end, it means that the engine oil
has overheated. If the vehicle has been
operated under normal driving
conditions, pull off the road, stop the
vehicle, and turn off the engine as
soon as possible.
See Engine Oil 0307.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
INSTRUMENTS AND CONTROLS 149
Engine Coolant
Temperature Warning Light
On some vehicles this light comes on
briefly while starting the vehicle. If it
does not, have the vehicle serviced by
the dealer. If the system is working
normally the indicator light goes off.
For vehicles with the reconfigurable
cluster, this light may not come on
when starting the vehicle.
Caution
The engine coolant temperature
warning light indicates that the
vehicle has overheated. Driving with
this light on can damage the engine
and it may not be covered by the
vehicle warranty. SeeEngine
Overheating 0321. The engine coolant temperature
warning light comes on when the
engine has overheated.
If this happens pull over and turn off
the engine as soon as possible. See
Engine Overheating
0321.
Tire Pressure Light
For vehicles with the Tire Pressure
Monitor System (TPMS), this light
comes on briefly when the engine is
started. It provides information about
tire pressures and the TPMS.
When the Light Is On Steady
This indicates that one or more of the
tires are significantly underinflated.
A Driver Information Center (DIC) tire
pressure message may also display.
Stop as soon as possible, and inflate the tires to the pressure value shown
on the Tire and Loading Information
label. See
Tire Pressure 0347.
When the Light Flashes First and
Then Is On Steady
If the light flashes for about a minute
and then stays on, there may be a
problem with the TPMS. If the
problem is not corrected, the light will
come on at every ignition cycle. See
Tire Pressure Monitor Operation 0350.
Engine Oil Pressure Light
Caution
Lack of proper engine oil
maintenance can damage the
engine. Driving with the engine oil
low can also damage the engine.
The repairs would not be covered
by the vehicle warranty. Check the
oil level as soon as possible. Add oil
if required, but if the oil level is
within the operating range and the
oil pressure is still low, have the
(Continued)

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
150 INSTRUMENTS AND CONTROLS
Caution (Continued)
vehicle serviced. Always follow the
maintenance schedule for changing
engine oil.
This light should come on briefly as
the engine is started. If it does not
come on, have the vehicle serviced by
your dealer.
If the light comes on and stays on, it
means that oil is not flowing through
the engine properly. The vehicle could
be low on oil and might have some
other system problem. See your dealer.
Low Fuel Warning Light
This light is near the fuel gauge and
comes on briefly when the ignition is
turned on as a check to show it is
working. For vehicles with a
reconfigurable cluster, this light is in
the display area and may not come on
when the ignition is turned on.
It also comes on when the fuel tank is
low on fuel. The light turns off when
fuel is added. If it does not, have the
vehicle serviced.
Auto Stop Mode (Uplevel
Cluster)
This light comes on when the engine
is in an Auto Stop.
SeeStarting the Engine (PLUG-IN Only)
0 218 orStarting the Engine (Gasoline
Only) 0221.
Security Light
On some vehicles the immobilizer
light should come on briefly as the
engine is started. If it does not come
on, have the vehicle serviced by your
dealer. If the system is working
normally, the indicator light turns off.
For vehicles with the reconfigurable
cluster, this light may not come on
when the engine is started.
If the light stays on and the engine
does not start, there could be a
problem with the theft-deterrent
system. See Immobilizer Operation
0 53.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
DRIVING AND OPERATING 217
.Check engine oil with every
refueling and add if necessary. Oil
and fuel consumption may be
higher than normal during the
first 2 400 km (1,500 mi).
. To break in new tires, drive at
moderate speeds and avoid hard
cornering for the first
300 km (200 mi). New tires do not
have maximum traction and may
tend to slip.
. New brake linings also need a
break–in period. Avoid making
hard stops during the first
300 km (200 mi). This is
recommended every time brake
linings are replaced.Ignition Positions
The vehicle has an electronic keyless
ignition with pushbutton start.
The Remote Keyless Entry (RKE)
transmitter must be in the vehicle for
the system to operate. If the
pushbutton start is not working, the
vehicle may be near a strong radio
antenna signal causing interference to
the Keyless Access system. See Remote
Keyless Entry (RKE) System Operation
0 35.
To shift out of P (Park), the ignition
must be on or in ACC/ACCESSORY,
and the brake pedal must be applied. Stopping the Engine/OFF (No
Indicator Lights) :
When the vehicle
is stopped, press ENGINE START/
STOP once to turn the engine off.
If the vehicle is in P (Park), the
ignition will turn off, and Retained
Accessory Power (RAP) will remain
active. See Retained Accessory Power
(RAP) 0224.
If the vehicle is not in P (Park), the
ignition will return to ACC/
ACCESSORY and display a message in
the Driver Information Center (DIC).
When the vehicle is shifted into
P (Park), the ignition will turn off.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake and
steering systems and disable the
airbags.
If the vehicle must be shut off in an
emergency: 1. Brake using a firm and steady pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
DRIVING AND OPERATING 287
by the vehicle warranty. If heavy
knocking is heard when using gasoline
rated at 93 octane, the engine needs
service.
Prohibited Fuels
Caution
Do not use fuels with any of the
following conditions; doing so may
damage the vehicle and void its
warranty:. For vehicles which 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, and
aniline. These fuels can
corrode metal fuel system
parts or damage plastic and
rubber parts.
. Fuel containing metals such
as methylcyclopentadienyl
manganese tricarbonyl
(Continued)
Caution (Continued)
(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.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that meet
California specifications. See the
underhood emission control label.
If this fuel is not available in states
adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting federal
specifications, but emission control
system performance may be affected.
The malfunction indicator lamp could
turn on and the vehicle may not pass a smog-check test. See
Malfunction
Indicator Lamp (Check Engine Light)
0 143. If this occurs, return to your
authorized dealer for diagnosis. If it is
determined that the condition is
caused by the type of fuel used,
repairs may not be covered by the
vehicle warranty.
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 Fuels” inFuel
0 286.
Fuel Additives
To keep fuel systems clean, TOP TIER
detergent gasoline is recommended.
See Fuel 0286.
If TOP TIER detergent gasoline is not
available, one bottle of GM Fuel
System Treatment Cleaner added to
the fuel tank at every engine oil
change, can help. GM Fuel System
Treatment Cleaner is the only gasoline
additive recommended by General
Motors. It is available at your dealer.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
292 DRIVING AND OPERATING
Backing Up
Hold the bottom of the steering wheel
with one hand. To move the trailer to
the left, move that hand to the left. To
move the trailer to the right, move
your hand to the right. Always back
up slowly and, if possible, have
someone guide you.
Making TurnsCaution
Making very sharp turns while
trailering could cause the trailer to
come in contact with the vehicle.
The vehicle could be damaged.
Avoid making very sharp turns
while trailering.
When turning with a trailer, make
wider turns than normal. Do this so
the trailer will not strike soft
shoulders, curbs, road signs, trees,
or other objects. Avoid jerky or sudden
maneuvers. Signal well in advance. If the trailer turn signal bulbs burn
out, the arrows on the instrument
cluster will still flash for turns. It is
important to check occasionally to be
sure the trailer bulbs are still working.
Driving on Grades
Reduce speed and shift to a lower gear
before
starting down a long or steep
downgrade. If the transmission is not
shifted down, the brakes might get hot
and no longer work well.
Vehicles can tow in D (Drive). Shift
the transmission to a lower gear if the
transmission shifts too often under
heavy loads and/or hilly conditions.
When towing at high altitude on steep
uphill grades, consider the following:
Engine coolant will boil at a lower
temperature than at normal altitudes.
If the engine is turned off immediately
after towing at high altitude on steep
uphill grades, the vehicle may show
signs similar to engine overheating. To
avoid this, let the engine run while
parked, preferably on level ground,
with the automatic transmission in
P (Park) for a few minutes before turning the engine off. If the overheat
warning comes on, see
Engine
Overheating 0321.
Parking on Hills
{Warning
Parking the vehicle on a hill with
the trailer attached can be
dangerous. If something goes
wrong, the rig could start to move.
People can be injured, and both the
vehicle and the trailer can be
damaged. When possible, always
park the rig on a flat surface.
If parking the rig on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn the
wheels into the curb if facing
downhill or into traffic if facing
uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the regular brakes
until the chocks absorb the load.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/14/17
DRIVING AND OPERATING 293
4. Reapply the brake pedal. Thenapply the parking brake and shift
into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine.
3. Shift into a gear.
4. Release the parking brake.
5. Let up on the brake pedal.
6. Drive slowly until the trailer is clear of the chocks.
7. Stop and have someone pick up and store the chocks.
Maintenance when Trailer
Towing
The vehicle needs service more often
when pulling a trailer. . Things that
are especially important in trailer
operation are automatic transmission
fluid, engine oil, axle lubricant, belts,
cooling system, and brake system. It is
a good idea to inspect these before
and during the trip. Check periodically to see that all hitch
nuts and bolts are tight.
Trailer Towing
(PLUG-IN Only)
The vehicle is neither designed nor
intended to tow a trailer.
Trailer Towing
(Gasoline Only)
Before pulling a trailer, three
important considerations have to do
with weight:
.
Weight of the trailer.
. Weight of the trailer tongue.
. Total weight on your vehicle's
tires.
Weight of the Trailer
How heavy can a trailer safely be?
It should never weigh more than
454 kg (1,000 lb). But even that can be
too heavy.
Safe trailering requires monitoring the
weight, speed, altitude, road grades,
outside temperature, the dimensions of the front of the trailer, and how
frequently the vehicle is used to pull a
trailer. Take into consideration any
special equipment on the vehicle, and
the amount of tongue weight the
vehicle can carry. See
“Weight of the
Trailer Tongue ”later in this section
for more information.
Trailer weight rating (TWR) is
calculated assuming the tow vehicle
has the driver, a front seat passenger,
and all required trailering equipment.
Weight of additional optional
equipment, passengers, and cargo in
the tow vehicle must be subtracted
from the trailer weight rating.
Ask your dealer for trailering
information or advice, or write us at
our Customer Assistance Offices. See
Customer Assistance Offices 0410.Weight of the Trailer Tongue
The tongue weight load (1) of any
trailer is very important because it is
also part of the vehicle weight. The
Gross Vehicle Weight (GVW) includes
the curb weight of the vehicle, any
cargo carried in it, and the people who
will be riding in the vehicle, as well as
trailer tongue weight. Vehicle options,

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
296 VEHICLE CARE
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 297
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 297
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 297
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 298
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 298
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 299
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 300
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 307
Engine Oil Life System . . . . . . . . . . . 309
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Engine Air Cleaner/Filter . . . . . . . . . 311
Cooling System (Gasoline Only) . . . . . . . . . . . . . . . . . 312
Cooling System (PLUG-IN Only) . . . . . . . . . . . . . . . . . 316
Engine Overheating . . . . . . . . . . . . . . 321
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 322
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 323 Battery - North America . . . . . . . . . 324
All-Wheel Drive . . . . . . . . . . . . . . . . . . 326
Starter Switch Check . . . . . . . . . . . . . 326
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . 327
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . 327
Wiper Blade Replacement . . . . . . . 327
Windshield Replacement . . . . . . . . 328
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 328
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . . . . . 329
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . 330
LED Lighting . . . . . . . . . . . . . . . . . . . . . 330
License Plate Lamp . . . . . . . . . . . . . . 330
Replacement Bulbs . . . . . . . . . . . . . . . 330
Electrical System
Electrical System Overload . . . . . . 331
Fuses and Circuit Breakers . . . . . . 331
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 332
Instrument Panel Fuse Block . . . . 335
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340 All-Season Tires . . . . . . . . . . . . . . . . . . 341
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 341
Low-Profile Tires . . . . . . . . . . . . . . . . . 342
Summer Tires . . . . . . . . . . . . . . . . . . . . 342
Tire Sidewall Labeling . . . . . . . . . . . 342
Tire Designations . . . . . . . . . . . . . . . . . 344
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . . . . . 345
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 347
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . 349
Tire Pressure Monitor System . . . 349
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 350
Tire Inspection . . . . . . . . . . . . . . . . . . . 353
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 353
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355
Buying New Tires . . . . . . . . . . . . . . . . 355
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 357
Uniform Tire Quality Grading . . . 357
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 359
Wheel Replacement . . . . . . . . . . . . . . 359
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 360
If a Tire Goes Flat . . . . . . . . . . . . . . . . 360
Tire Sealant and Compressor Kit . . . . . . . . . . . . . . . . . 362
Storing the Tire Sealant and Compressor Kit . . . . . . . . . . . . . . . . . 368

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-11292458) -
2018 - crc - 2/15/17
VEHICLE CARE 307
1. Engine Coolant Surge Tank andPressure Cap.
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
2. Engine Air Cleaner/Filter 0311.
3. Engine Cooling Fan (Out of View).
See Cooling System (Gasoline
Only) 0312 orCooling System
(PLUG-IN Only) 0316.
4. Engine Oil Fill Cap. See Engine Oil
0 307.
5. Engine Oil Dipstick. See Engine
Oil 0307.
6. Remote Positive (+) Battery Terminal. See Jump Starting -
North America 0374.
7. Engine Compartment Fuse Block
0332.
8. Brake Fluid Reservoir. See Brake
Fluid 0323.
9. Windshield Washer Fluid Reservoir. See Washer Fluid
0 322. 10. Remote Negative (-) Battery
Terminal. See Jump Starting -
North America 0374.
Engine Oil
To ensure proper engine performance
and long life, careful attention must
be paid to engine oil. Following these
simple, but important steps will help
protect your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“Selecting the Right Engine Oil” in
this section.
. Check the engine oil level regularly
and maintain the proper oil level.
See “Checking Engine Oil” and
“When to Add Engine Oil” later in
this section.
. Change the engine oil at the
appropriate time. See Engine Oil
Life System 0309.
. Always dispose of engine oil
properly. See “What to Do with
Used Oil” in this section.
Checking Engine Oil
Check the engine oil level regularly,
every 650 km (400 mi), especially prior
to a long trip. The engine oil dipstick
handle is a loop. See Engine
Compartment Overview 0300 for the
location.
{Warning
The engine oil dipstick handle may
be hot; it could burn you. Use a
towel or glove to touch the dipstick
handle.
If a low oil Driver Information Center
(DIC) message displays, check the oil
level.
Follow these guidelines:
. To get an accurate reading, park
the vehicle on level ground. Check
the engine oil level after the
engine has been off for at least
two hours. Checking the engine oil
level on steep grades or too soon
after engine shutoff can result in
incorrect readings. Accuracy