2021 RAM 1500 ignition

SERVICING AND MAINTENANCE415
DIESEL EXHAUST FLUID
Diesel Exhaust Fluid (DEF) sometimes known
simply by the name of its active component,
UREA—is a key component of Selective Catalytic
Reduction (SCR) systems, which help diesel
vehicles meet stringent emission regulations.
DEF is a liquid reducing agent that reacts with
engine exhaust in the presence of a catalyst to
convert smog-forming nitrogen oxides (NOx)
into harmless nitrogen and water vapor.
Refer to Engine Fluids And Lubricants
Úpage 475 for further information.
AIR CONDITIONER MAINTENANCE
For best possible performance, your air
conditioner should be checked and serviced by
an authorized dealer at the start of each warm
season. This service should include cleaning of
the condenser fins and a performance test.
Drive belt tension should also be checked at
this time.
Refrigerant Recovery And Recycling —
R–1234yf
R–1234yf Air Conditioning Refrigerant is a
hydrofluoroolefin (HFO) that is endorsed by the
Environmental Protection Agency and is an
ozone-friendly substance with a low
global-warming potential. It is recommended
that air conditioning service be performed by an
authorized dealer using recovery and recycling
equipment.
NOTE:
Use only FCA approved A/C system PAG
compressor oil, and refrigerants.
Cabin Filter Replacement (A/C Air Filter)
For the proper maintenance intervals
Úpage 395.
WARNING!
Use only refrigerants and compressor lubri -
cants approved by FCA for your air condi -
tioning system. Some unapproved
refrigerants are flammable and can
explode, injuring you. Other unapproved
refrigerants or lubricants can cause the
system to fail, requiring costly repairs.
Refer to Warranty Information Book, for
further warranty information.
The air conditioning system contains refrig -
erant under high pressure. To avoid risk of
personal injury or damage to the system,
adding refrigerant or any repair requiring
lines to be disconnected should be done by
an experienced technician.
CAUTION!
Do not use chemical flushes in your air
conditioning system as the chemicals can
damage your air conditioning components.
Such damage is not covered by the New
Vehicle Limited Warranty.
WARNING!
Do not remove the cabin air filter while the
vehicle is running, or while the ignition is in
the ACC or ON/RUN mode. With the cabin air
filter removed and the blower operating, the
blower can contact hands and may propel dirt
and debris into your eyes, resulting in
personal injury.
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SERVICING AND MAINTENANCE417
6. Remove the cabin air filter by pulling it
straight out of the housing.

Cabin Air Filter

7. Install the cabin air filter with the arrow on the filter pointing toward the floor. When
installing the filter cover, press on each end
until you hear an audible click.
8. Reinstall the glove compartment on the hinges. 9. Pull the tension tether outward and reinstall
the glove compartment past the travel stops
by pushing in on the glove compartment
sides.

Glove Compartment

NOTE:
Ensure the glove compartment door hinges and
glove compartment travel stops are fully
engaged.
10. Reattach the glove compartment tension tether by inserting the tether clip in the
glove compartment and sliding the clip
away from the face of the glove
compartment door.ACCESSORY DRIVE BELT INSPECTION
When inspecting accessory drive belts, small
cracks that run across the ribbed surface of the
belt from rib to rib, are considered normal. This
is not a reason to replace the belt. However,
cracks running along a rib (not across) are not
normal. Any belt with cracks running along a rib
must be replaced. Also have the belt replaced if
it has excessive wear, frayed cords or severe
glazing.CAUTION!
The cabin air filter is identified with an arrow
to indicate airflow direction through the filter.
Failure to properly install the filter will result
in the need to replace it more often.
1 — Glove Compartment Travel Stop
2 — Glove Compartment Tension Tether
3 — Glove Compartment Door
WARNING!
Do not attempt to inspect an accessory
drive belt with vehicle running.
When working near the radiator cooling fan,
disconnect the fan motor lead. The fan is
temperature controlled and can start at any
time regardless of ignition mode. You could
be injured by the moving fan blades.
You can be badly injured working on or
around a motor vehicle. Only do service
work for which you have the knowledge and
the proper equipment. If you have any
doubt about your ability to perform a
service job, take your vehicle to a compe -
tent mechanic.
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SERVICING AND MAINTENANCE421
overheating. If this occurs, stop the vehicle, turn
off the engine and allow it to cool. Service,
including a tune-up to manufacturer's
specifications, should be obtained immediately.
To minimize the possibility of catalytic converter
damage:
Do not interrupt the ignition when the trans -
mission is in gear and the vehicle is in
motion.
Do not try to start the vehicle by pushing or
towing the vehicle.
Do not idle the engine with any ignition
components disconnected or removed, such
as when diagnostic testing, or for prolonged
periods during very rough idle or malfunc -
tioning operating conditions.
COOLING SYSTEM Engine Coolant Checks
Check the engine coolant (antifreeze)
protection every 12 months (before the onset of
freezing weather, where applicable). If the
engine coolant is dirty or rusty in appearance,
the system should be drained, flushed and
refilled with fresh coolant. Check the front of the
A/C condenser (if equipped) or radiator for any
accumulation of bugs, leaves, etc. If dirty, clean
by gently spraying water from a garden hose
vertically down the face of the A/C condenser (if
equipped) or the back of the radiator core.
Check the engine cooling system hoses for
brittle rubber, cracking, tears, cuts and
tightness of the connection at the coolant
recovery bottle and radiator. Inspect the entire
system for leaks.
DO NOT REMOVE THE COOLANT PRESSURE CAP
WHEN THE COOLING SYSTEM IS HOT. WARNING!
You or others can be badly burned by hot
engine coolant (antifreeze) or steam from
your radiator. If you see or hear steam
coming from under the hood, do not open
the hood until the radiator has had time to
cool. Never open a cooling system pressure
cap when the radiator or coolant bottle is
hot.
Keep hands, tools, clothing, and jewelry
away from the radiator cooling fan when
the hood is raised. The fan starts automati -
cally and may start at any time, whether the
engine is running or not.
When working near the radiator cooling fan,
disconnect the fan motor lead or turn the
ignition to the OFF mode. The fan is
temperature controlled and can start at any
time the ignition is in the ON mode.
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SERVICING AND MAINTENANCE427
Drain And Refill
For the proper maintenance intervals
Úpage 395.
Lubricant Selection
For further information Ú page 478.
NOTE:
The presence of water in the gear lubricant will
result in corrosion and possible failure of differ -
ential components. Operation of the vehicle in
water, as may be encountered in some
off-highway types of service, will require
draining and refilling the axle to avoid damage.
Limited-Slip Differentials
Rear axles equipped with a Limited Slip
Differential require that 5 oz. (148 ml) Mopar
Limited Slip Additive be added to the gear
lubricant Ú page 478. The Mopar Limited Slip
Additive should be added to the gear lubricant
whenever a fluid change is made to an axle
equipped with a Limited Slip Differential. NOTE:
When refilling a limited slip differential axle
which requires a friction modification additive,
the additive should be added before the gear
lubricant to ensure proper additive fill.TRANSFER CASE
Fluid Level Check
This fluid level can be checked by removing the
filler plug. The fluid level should be to the
bottom edge of the filler plug hole (or within
1/8 inch of the bottom) with the vehicle in a
level position.
Drain And Refill
For the proper maintenance intervals
Ú
page 395.
Selection Of Lubricant
Use only the recommended fluid Ú page 478.
FUSES
General Information
WARNING!
When replacing a blown fuse, always use
an appropriate replacement fuse with the
same amp rating as the original fuse. Never
replace a fuse with another fuse of higher
amp rating. Never replace a blown fuse with
metal wires or any other material. Do not
place a fuse inside a circuit breaker cavity
or vice versa. Failure to use proper fuses
may result in serious personal injury, fire
and/or property damage.
Before replacing a fuse, make sure that the
ignition is off and that all the other services
are switched off and/or disengaged.
If the replaced fuse blows again, contact an
authorized dealer.
If a general protection fuse for safety
systems (air bag system, braking system),
power unit systems (engine system, trans -
mission system) or steering system blows,
contact an authorized dealer.
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SERVICING AND MAINTENANCE433
F09––Spare
F10 40 Amp Green –HVAC Blower Motor
F11 –5 Amp Tan Output to Under-hood Power Distribution Center (UPDC) Run Coil
F12 –25 Amp Clear Mod Audio Amplifier / Active Noise Cancellation / SW Inverter
F13 –20 Amp Yellow Mod Seat Heater Front (Driver)
F14 –15 Amp Blue Mod Seat Heater Front (Steering Wheel)
F15 ––Spare
F16 ––Spare
F17 –20 Amp Yellow LT Spot Lamp — If Equipped
F18 30 Amp Pink –Motor Sunshade Sunroof
F19 ––Spare
F20 –20 Amp Yellow Comfort Rear Seat Module (CRSM) (Heat Rear RT)
F21 ––Spare
F22 ––Spare
F23 ––Spare
F24 –15 Amp Blue Mod RF Hub / Mod Ignition / Mod Cluster
F25 40 Amp Green –Mod Integrated Trailer Brake
F26 –15 Amp Blue Mod Cluster CCN / Mod Cyber Security
F27 –5 Amp Tan Mod Cluster CCN / Mod SGW
F28 –10 Amp Red Mod ORC
CavityCartridge Fuse Micro Fuse Description
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486
Fluid Leaks
.................................................... 371Fluid Level Checks Brake........................................................ 425Fluid, Brake................................................... 478Fog Lights............................................... 55, 441Fold-Flat Seats................................................. 34Forward Collision Warning............................. 324Four Wheel Drive........................................... 161Four-Way Hazard Flasher............................... 373Freeing A Stuck Vehicle................................. 391Front Axle (Differential).................................. 426Fuel............................................ 210, 468, 471Adding............................................. 208, 210Additives................................................... 469Clean Air.................................................... 469Ethanol...................................................... 469Filter.......................................................... 412Gasoline.................................................... 468Light.......................................................... 131Materials Added........................................ 469Methanol................................................... 469Octane Rating........................ 468, 469, 475Requirements........................ 468, 471, 474Specifications............................................ 471Tank Capacity............................................ 474Fuses............................................................. 427
G
Garage Door Opener (HomeLink)..................... 49Gasoline, Clean Air........................................ 469Gasoline, Reformulated................................ 469GaugesVoltage..................................................... 146Glass Cleaning.............................................. 466Grocery Bag Retainer....................................... 39Gross Axle Weight Rating.............................. 215Gross Vehicle Weight Rating......................... 214GuideBody Builders.............................................. 11GVWR............................................................ 213
H
HazardDriving Through Flowing, Rising, Or Shallow Standing Water
.................................... 234Hazard Warning Flashers.............................. 373Head Restraints............................................... 40Head Rests...................................................... 40Headlights.................................................... 439Cleaning................................................... 462High Beam................................................... 53High Beam/Low Beam Select Switch.......... 53Lights On Reminder..................................... 55Passing........................................................ 54Switch.......................................................... 52
Heated Mirrors.................................................48Heated Seats...................................................38Heater, Engine Block..................................... 150High Beam/Low Beam Select (Dimmer)
Switch..............................................................53Hill Descent Control...................................... 315Hill Descent Control Indicator....................... 315Hill Start Assist.............................................. 317HitchesTrailer Towing........................................... 218HomeLink (Garage Door Opener).....................49Hood Prop........................................................84Hood Release...................................................84
I
Ignition.............................................................21Switch..........................................................21Illuminated Entry..............................................58Inside Rearview Mirror.................... 44, 45, 373Instrument Cluster............................... 110, 113Descriptions............................ 110, 113, 136Display...................................................... 114Instrument Panel Lens Cleaning................... 465Integrated Trailer Brake Control.................... 223Interior Appearance Care.............................. 464Interior Lights...................................................57Intervention Regeneration Strategy..... 121, 414Inverter Outlet (115V)......................................75

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