low oil pressure GMC SIERRA 2021 Owner's Manual

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
20 Keys, Doors, and Windows
Remote Vehicle Start
If equipped with the remote start feature,
the climate control system will come on
when the vehicle is started remotely,
depending on the outside temperature.
The rear defog and heated and ventilated
seats, if equipped, may also come on. See
Heated and Ventilated Front Seats052 and
Vehicle Personalization 0131.
If equipped, the automatic heated steering
wheel may also come on. See Heated
Steering Wheel 0100.
Laws in some communities may restrict the
use of remote starters. Check local
regulations for any requirements on remote
starting of vehicles.
Do not use remote start if the vehicle is low
on fuel. The vehicle may run out of fuel.
The vehicle cannot be remote started if:
.The RKE transmitter is inside the vehicle
or if the key is in the ignition.
.The hood is not closed.
.There is an emission control system
malfunction and the lamp is on.
.The ignition is in any mode other
than off.
.The hazard warning flashers are on.
.Two remote starts or a remote start with
an extension have been used.
.The vehicle is not in P (Park).
The engine will turn off during a remote
vehicle start if:
.The coolant temperature gets too high.
.The oil pressure gets low.
The RKE transmitter range may be reduced
while the vehicle is running.
Other conditions can affect the performance
of the transmitter. See Remote Keyless Entry
(RKE) System 010.
Starting the Engine Using Remote Start
1. Press and release
Q.
2. Immediately press and hold
/until the
turn signal lamps flash or for at least
four seconds.
When the vehicle starts, the parking
lamps will turn on. The doors will be
locked and the climate control system
may come on. The engine will continue to run for
15 minutes. After 30 seconds, repeat
Steps 1 and 2 for a 15-minute time
extension.
Turn the ignition on to operate the vehicle.
Extending Engine Run Time
The engine run time can be extended by
15 minutes, for a total of 30 minutes,
if during the first 15 minutes Steps 1 and 2
are repeated while the engine is still
running. An extension can be requested
30 seconds after starting.
A maximum of two remote starts, or a
single start with an extension, is allowed
between ignition cycles.
The vehicle's ignition must be turned on and
then back off to use remote start again.
Canceling a Remote Start
To cancel a remote start, do one of the
following:
.Press and hold/until the parking lamps
turn off.
.Turn on the hazard warning flashers.
.Turn the ignition on and then off.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Instruments and Controls 99
Instruments and Controls
Controls
Steering Wheel Adjustment . . . . . . . . . . . 100
Steering Wheel Controls . . . . . . . . . . . . . . 100
Heated Steering Wheel . . . . . . . . . . . . . . . . 100
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Windshield Wiper/Washer . . . . . . . . . . . . . 101
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Power Outlets . . . . . . . . . . . . . . . . . . . . . . . . . 102
Wireless Charging . . . . . . . . . . . . . . . . . . . . . 103
Warning Lights, Gauges, and Indicators
Warning Lights, Gauges, andIndicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Instrument Cluster . . . . . . . . . . . . . . . . . . . . 106
Speedometer . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . . 110
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Fuel Gauge . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110
Engine Oil Pressure Gauge . . . . . . . . . . . . . 111
Engine Coolant Temperature Gauge . . . . 112
Voltmeter Gauge . . . . . . . . . . . . . . . . . . . . . . . 113
Seat Belt Reminders . . . . . . . . . . . . . . . . . . . . 113
Airbag Readiness Light . . . . . . . . . . . . . . . . . 114
Passenger Airbag Status Indicator . . . . . . 114
Charging System Light . . . . . . . . . . . . . . . . . 115 Malfunction Indicator Lamp (Check
Engine Light) . . . . . . . . . . . . . . . . . . . . . . . . . 115
Brake System Warning Light . . . . . . . . . . . 117
Electric Parking Brake Light . . . . . . . . . . . . 117
Service Electric Parking Brake Light . . . . 118
Antilock Brake System (ABS) Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Four-Wheel-Drive Light . . . . . . . . . . . . . . . . . 118
Tow/Haul Mode Light . . . . . . . . . . . . . . . . . 119
Hill Descent Control Light . . . . . . . . . . . . . . 119
Lane Keep Assist (LKA) Light . . . . . . . . . . . 119
Vehicle Ahead Indicator . . . . . . . . . . . . . . . . 119
Pedestrian Ahead Indicator . . . . . . . . . . . . 119
Traction Off Light . . . . . . . . . . . . . . . . . . . . . . 120
Traction Control System (TCS)/Electronic Stability Control Light . . . . . . . . . . . . . . . 120
Electronic Stability Control (ESC) Off Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Engine Coolant Temperature Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Driver Mode Control Light . . . . . . . . . . . . . 121
Tire Pressure Light . . . . . . . . . . . . . . . . . . . . . 122
Engine Oil Pressure Light (Uplevel Cluster) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Low Fuel Warning Light . . . . . . . . . . . . . . . . 122
Security Light . . . . . . . . . . . . . . . . . . . . . . . . . . 122
High-Beam On Light . . . . . . . . . . . . . . . . . . . 123
Front Fog Lamp Light . . . . . . . . . . . . . . . . . . 123
Lamps On Reminder . . . . . . . . . . . . . . . . . . . 123
Cruise Control Light . . . . . . . . . . . . . . . . . . . . 123 Door Ajar Light . . . . . . . . . . . . . . . . . . . . . . . . 124
Information Displays
Driver Information Center (DIC) (Base
Level) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Driver Information Center (DIC) (Midlevel and Uplevel) . . . . . . . . . . . . . . . 125
Head-Up Display (HUD) . . . . . . . . . . . . . . . . 128
Vehicle Messages
Vehicle Messages . . . . . . . . . . . . . . . . . . . . . . 130
Engine Power Messages . . . . . . . . . . . . . . . . 131
Vehicle Speed Messages . . . . . . . . . . . . . . . 131
Vehicle Personalization
Vehicle Personalization . . . . . . . . . . . . . . . . . 131
Universal Remote System
Universal Remote System . . . . . . . . . . . . . 136
Universal Remote System Programming . . . . . . . . . . . . . . . . . . . . . . . . 136
Universal Remote System Operation . . . 138

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Instruments and Controls 111
English Uplevel Shown, Midlevel and BaseLevel Similar
When the ignition is on, the fuel gauge
indicates about how much fuel is left in
the tank.
There is an arrow near the fuel gauge
pointing to the side of the vehicle the fuel
door is on.
When the indicator nears empty, the low
fuel light comes on. There still is a little fuel
left, but the vehicle should be refueled soon.
Here are three things that some owners ask
about. None of these show a problem with
the fuel gauge:
.It takes a little more, or less fuel to fill up
than the gauge indicated. For example,
the gauge may have indicated the tank
was half full, but it actually took a little
more, or less than half the tank's capacity
to fill the tank.
.The gauge moves a little while turning a
corner, speeding up or braking.
.The gauge takes a few seconds to
stabilize after the ignition is turned on
and goes back to empty when the
ignition is turned off.
Engine Oil Pressure Gauge
Uplevel Metric Shown, Base Level and Midlevel Similar
Uplevel English Shown, Base Level and
Midlevel Similar
The engine oil pressure gauge shows the
engine oil pressure in kPa (kilopascals)
or psi (pounds per square inch) when the
engine is running.
Oil pressure can vary with engine speed,
outside temperature, coolant temperature,
and oil viscosity.
On some models, the oil pump will vary
engine oil pressure according to engine
needs. Oil pressure may change quickly as
the engine speed or load varies. This is
normal. If the oil pressure warning light or
Driver Information Center (DIC) message

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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112 Instruments and Controls
indicates oil pressure outside the normal
operating range, check the vehicle's oil as
soon as possible.
SeeEngine Oil 0330.
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.
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
Engine Coolant Temperature
Gauge
Metric Uplevel Shown, Midlevel and Base Level Similar
English Uplevel Shown, Midlevel and Base Level Similar
This gauge measures the temperature of the
vehicle's engine coolant.
While driving under normal operating
conditions, if the needle moves into the red
warning area, the engine is too hot. Pull off
the road, stop the vehicle, and turn off the
engine as soon as possible.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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122 Instruments and Controls
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. SeeTire Pressure
0 367.
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
0 369.
Engine Oil Pressure Light (Uplevel
Cluster)
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.
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.
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.
Security Light

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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124 Instruments and Controls
Door Ajar Light
This light comes on when a door is open or
not securely latched. Before driving, check
that all doors are properly closed.
Information Displays
Driver Information Center (DIC)
(Base Level)
The DIC displays are shown in the center of
the instrument cluster. The displays show
the status of many vehicle systems. The trip
odometer reset stem in the instrument
cluster is used to access the DIC menu
items.
If the vehicle has a diesel engine, see the
Duramax diesel supplement for more
information.
DIC Menu Items
Turn the trip odometer reset stem to scroll
through the following menu items:
.Digital Speedometer
.Trip 1/2
.Fuel Range
.Tire Pressure
.Remaining Oil Life
.Air Filter Life
.Brake Pad Life
Digital Speedometer
The speedometer shows how fast the
vehicle is moving in either kilometers per
hour (km/h) or miles per hour (mph). The
speedometer cannot be reset.
Trip 1 or 2 and Average Fuel Economy
Turn the trip odometer reset stem until TRIP
1 or TRIP 2 displays. The current distance
traveled, in either kilometers (km) or
miles (mi), since the last reset for the trip
odometer is shown, as well as the average
fuel economy. The trip odometer and the
average fuel economy can be reset by
pressing and holding the trip odometer
reset stem. Fuel Range
This display shows the approximate distance
the vehicle can be driven without refueling.
The fuel range estimate is based on an
average of the vehicle's fuel economy over
recent driving history and the amount of
fuel remaining in the fuel tank. Fuel range
cannot be reset.
Tire Pressure
Turn the trip odometer reset stem until a
vehicle with the approximate pressures of all
four tires displays. Tire pressure is displayed
in either kilopascal (kPa) or in pounds per
square inch (psi).
See
Tire Pressure Monitor System 0368 and
Tire Pressure Monitor Operation 0369.
Remaining Oil Life
Turn the trip odometer reset stem until
REMAINING OIL LIFE displays. An estimate of
the oil's remaining useful life is shown.
REMAINING OIL LIFE 99% means 99% of the
current oil life remains.
When the remaining oil life is low, the
CHANGE ENGINE OIL SOON message will
appear on the display. The oil should be
changed as soon as possible. See Engine Oil
0 330. In addition to the engine oil life

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Instruments and Controls 127
than when the oil has just been changed.
It cannot be reset accurately until the next
oil change. To reset, seeEngine Oil Life
System 0332.
Tire Pressure : Shows the approximate
pressures of all four tires. Tire pressure is
displayed in either kilopascal (kPa) or in
pounds per square inch (psi). If the pressure
is low, the value for that tire is shown in
amber. See Tire Pressure Monitor System
0 368 and
Tire Pressure Monitor Operation 0369.
Air Filter Life : Shows an estimate of the
engine air filter’s remaining useful life and
the state of the system. Engine Air Filter Life
95% means 95% of the current air filter life
remains. Messages will display based on the
engine air filter life and the state of the
system. When the REPLACE AT NEXT OIL
CHANGE message displays, the engine air
filter should be replaced at the time of the
next oil change. When the REPLACE SOON
message displays, the engine air filter
should be replaced at the earliest
convenience.
The Air Filter Life display must be reset after
the engine air filter replacement. To reset,
see Engine Air Filter Life System 0333. Brake Pad Life :
This displays an estimate of
the remaining life of the front and rear
brake pads. Messages will display based on
brake pad wear and the state of the system.
Reset the Brake Pad Life display after
replacing the brake pads. See Brake Pad Life
System 0342.
Fuel Economy : Displays average fuel
economy, the best fuel economy over the
selected distance, and a bar graph showing
instantaneous fuel economy.
Press the thumbwheel to change the
selected distance. Press and hold the
thumbwheel while this display is active to
reset the best fuel economy and average
fuel economy. This display can also be reset
by selecting reset in the menu.
Engine Hours (Hourmeter) : Shows the total
number of hours the engine has run. This
display also shows the engine idle hours.
Transmission Fluid Temperature : Shows the
temperature of the automatic transmission
fluid in either degrees Celsius (°C) or degrees
Fahrenheit (°F).
Trailer Brake : On vehicles with the
Integrated Trailer Brake Control (ITBC)
system, the trailer brake display appears in
the DIC. TRAILER GAIN shows the trailer gain setting.
This setting can be adjusted from 0.0 to 10.0
with either a trailer connected or
disconnected.
TRAILER OUTPUT shows the power output to
the trailer any time a trailer with electric
brakes is connected. Output is displayed as a
bar graph. Dotted lines may appear in the
OUTPUT display if a trailer is not connected.
Off Road :
Displays vehicle pitch and roll
information, road wheel angle, and
four-wheel drive (4WD) status.
Follow Distance : If equipped, the current
follow time to the vehicle ahead is displayed
as a time value on this page.
Driver Assistance : If equipped, shows
information for Lane Keep Assist (LKA) and
Forward Collision Alert (FCA).
Info Page Options : Scroll to choose which
info pages appear on the DIC. Press the
thumbwheel to select or deselect.
Blank Page : Shows no information.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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330 Vehicle Care
1. Remote Negative (–) Location. SeeJump
Starting - North America 0391.
2. Positive (+) Terminal (Under Cover). See Jump Starting - North America 0391.
3. Battery - North America 0343.
4. Engine Compartment Fuse Block 0353.
5. Engine Oil Dipstick. See “Checking Engine
Oil” under Engine Oil 0330.
6. Engine Cooling Fans (Out of View). See Cooling System 0335.
7. Engine Oil Fill Cap. See “When to Add
Engine Oil” underEngine Oil 0330.
8. Coolant Surge Tank and Pressure Cap. See Cooling System 0335.
9. Engine Air Cleaner/Filter 0334.
10. Brake Fluid Reservoir. See Brake Fluid
0 343.
11. Windshield Washer Fluid Reservoir. See “Adding Washer Fluid” underWasher
Fluid 0340.
Engine Oil
For diesel engine vehicles, see “Engine Oil”
in the Duramax diesel supplement. 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” in this section.
.Change the engine oil at the appropriate
time. SeeEngine Oil Life System 0332.
.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 0325 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 improves when
checking a cold engine prior to starting.
Remove the dipstick and check the level.
.If unable to wait two hours, the engine
must be off for at least 15 minutes if the
engine is warm, or at least 30 minutes if
the engine is not warm. Pull out the
dipstick, wipe it with a clean paper towel
or cloth, then push it back in all the way.
Remove it again, keeping the tip down,
and check the level.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
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Vehicle Care 337
Check to see if coolant is visible in the
coolant surge tank. If the coolant inside the
coolant surge tank is boiling, wait until it
cools down. The coolant level should be at
or above the indicated mark. If it is not,
there may be a leak in the cooling system.
If coolant is visible but the coolant level is
not at or above the indicated mark, see the
following sections on how to add coolant to
the coolant surge tank following.
Automatic Coolant Service Fill
Instructions (L3B Engine)
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. Remove the coolant surge tank pressure cap when the cooling system, including
the coolant surge tank pressure cap and
upper radiator hose, is no longer hot.
Turn the pressure cap; slowly
counterclockwise about one full turn. If a
hiss is heard, wait for that to stop.
A hiss means there is still some
pressure left. 2. Keep turning the pressure cap slowly,
and remove it.
3. Fill the coolant surge tank with the proper mixture to the indicated mark.
4. Connect the vehicle to a battery charger.
5. Set the ignition to service mode, see Ignition Positions (Keyless Access) 0230
or
Ignition Positions (Key Access) 0229.
6. Turn off the air conditioning.
7. Set the parking brake.
8. At the same time, press the accelerator and the brake for automatic vehicles for
two seconds, then release.
9. Listen for pump activation and movement of the control valves while
watching the level of the coolant in the
surge tank. Add fluid as the level drops
below the indicated mark on the surge
tank. Allow 15 minutes for the fill and air
removal process to complete.
10. Reinstall the surge tank cap.
If the tank empties, turn the ignition off,
allow the Electronic Control Module (ECM) to
go to sleep, about two minutes, refill to the
indicated mark, and repeat Steps 5–9.
How to Add Coolant to the Coolant
Surge Tank for Gasoline Engines
Except L3B
If the vehicle has a diesel engine, see
“Cooling System” in the Duramax diesel
supplement for the proper coolant fill
procedure.
{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
Plain water, or other liquids such as
alcohol, can boil before the proper
coolant mixture will. With plain water or
the wrong mixture, the engine could get
too hot but there would not be an
overheat warning. The engine could catch
fire and you or others could be burned.

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Vehicle Care 403
and contaminate the fluid. Contaminated
fluid will decrease the life of the transfer
case and/or axles and should be replaced.
Sheet Metal Damage
If the vehicle is damaged and requires sheet
metal repair or replacement, make sure the
body repair shop applies anti-corrosion
material to parts repaired or replaced to
restore corrosion protection.
Original manufacturer replacement parts will
provide the corrosion protection while
maintaining the vehicle warranty.
Finish Damage
Quickly repair minor chips and scratches
with touch-up materials available from your
dealer to avoid corrosion. Larger areas of
finish damage can be corrected in your
dealer's body and paint shop.
Chemical Paint Spotting
Airborne pollutants can fall upon and attack
painted vehicle surfaces causing blotchy,
ring-shaped discolorations, and small,
irregular dark spots etched into the paint
surface. Refer to“Finish Care”previously in
this section.
Interior Care
To prevent dirt particle abrasions, regularly
clean the vehicle's interior. Immediately
remove any soils. Newspapers or dark
garments can transfer color to the vehicle’s
interior.
Use a soft bristle brush to remove dust from
knobs and crevices on the instrument
cluster. Using a mild soap solution,
immediately remove hand lotions,
sunscreen, and insect repellent from all
interior surfaces or permanent damage may
result.
Use cleaners specifically designed for the
surfaces being cleaned to prevent
permanent damage. Apply cleaners directly
to the cleaning cloth. Do not spray cleaners
on any switches or controls. Remove
cleaners quickly.
Before using cleaners, read and follow all
safety instructions on the label. While
cleaning the interior, open the doors and
windows to get proper ventilation. To prevent damage, do not clean the
interior using the following cleaners or
techniques:
.Never use a razor or any other sharp
object to remove soil from any interior
surface.
.Never use a brush with stiff bristles.
.Never rub any surface aggressively or
with too much pressure.
.Do not use laundry detergents or
dishwashing soaps with degreasers. For
liquid cleaners, use approximately
20 drops per 3.8 L (1 gal) of water.
A concentrated soap solution will create
streaks and attract dirt. Do not use
solutions that contain strong or
caustic soap.
.Do not heavily saturate the upholstery
when cleaning.
.Do not use solvents or cleaners containing
solvents.
Interior Glass
To clean, use a terry cloth fabric dampened
with water. Wipe droplets left behind with a
clean dry cloth. If necessary, use a
commercial glass cleaner after cleaning with
plain water.