2021 RAM CHASSIS CAB check engine

SERVICING AND MAINTENANCE387
(Continued)
BRAKE SYSTEM
In order to ensure brake system performance,
all brake system components should be
inspected periodically Ú page 354.
Fluid Level Check — Brake Master Cylinder
The fluid level of the master cylinder should be
checked when performing under the hood
service or immediately if the brake system
warning lamp indicates system failure.

If necessary, add fluid to bring level within the
designated marks on the side of the reservoir of the
brake master cylinder. Be sure to clean the top of
the master cylinder area before removing cap.
With disc brakes the fluid level can be expected
to fall as the brake linings wear. However, an
unexpected drop in fluid level may be caused by
a leak and a system check should be conducted.

For further information Ú
page 444.
AUTOMATIC TRANSMISSION
Special Additives

The manufacturer strongly recommends against
using any special additives in the transmission.
Automatic Transmission Fluid (ATF) is an
engineered product and its performance may be
impaired by supplemental additives. Therefore,
do not add any fluid additives to the transmission.
The only exception to this policy is the use of special
dyes for diagnosing fluid leaks in six-speed
transmissions. Avoid using transmission sealers as
they may adversely affect seals.

WARNING!
Riding the brakes can lead to brake failure
and possibly a collision. Driving with your foot
resting or riding on the brake pedal can result
in abnormally high brake temperatures,
excessive lining wear, and possible brake
damage. You would not have your full braking
capacity in an emergency.WARNING!
Use only manufacturer's recommended
brake fluid Úpage 444. Using the wrong
type of brake fluid can severely damage
your brake system and/or impair its perfor -
mance. The proper type of brake fluid for
your vehicle is also identified on the original
factory installed hydraulic master cylinder
reservoir.

To avoid contamination from foreign matter
or moisture, use only new brake fluid or fluid
that has been in a tightly closed container.
Keep the master cylinder reservoir cap
secured at all times. Brake fluid in a open
container absorbs moisture from the air
resulting in a lower boiling point. This may
cause it to boil unexpectedly during hard or
prolonged braking, resulting in sudden brake
failure. This could result in a collision.

Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine
parts, causing the brake fluid to catch fire.
Brake fluid can also damage painted and
vinyl surfaces, care should be taken to
avoid its contact with these surfaces.
Do not allow petroleum based fluid to
contaminate the brake fluid. Brake seal
components could be damaged, causing
partial or complete brake failure. This could
result in a collision.
WARNING! (Continued)
8

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388SERVICING AND MAINTENANCE
Fluid Level Check — Eight-Speed
Transmission
The fluid level is preset at the factory and does
not require adjustment under normal operating
conditions. Routine fluid level checks are not
required, therefore the transmission has no
dipstick. An authorized dealer can check your
transmission fluid level using special service
tools.
If you notice fluid leakage or transmission
malfunction, visit an authorized dealer
immediately to have the transmission fluid
level checked. Operating the vehicle with
an improper fluid level can cause severe
transmission damage.
Fluid Level Check — Six-Speed
Transmission
It is best to check the fluid level when the
transmission is at normal operating
temperature (158-176°F / 70-80°C). This
normally occurs after at least 15 miles (25 km)
of driving. At normal operating temperature the
fluid cannot be held comfortably between the
fingertips. You can read the transmission sump
temperature in the instrument cluster screen
Ú page 90. Use the following procedure to check the
transmission fluid level properly:

1. Monitor the transmission temperature
using the instrument cluster display, and
operate the vehicle as required to reach
the normal operating temperature. If the
transmission is not functioning properly, or
the vehicle cannot be driven, see the NOTE
and CAUTION below about checking the
fluid level at colder temperatures.

2. Park the vehicle on level ground.
3. Run the engine at normal idle speed for at least 60 seconds, and leave the engine
running for the rest of this procedure.
4. Fully apply the parking brake, and press the brake pedal.
5. Place the gear selector momentarily into each gear position (allowing time for the
transmission to fully engage in each
position), ending with the transmission in
PARK.
6. Remove the dipstick, wipe it clean and reinsert it until seated.
CAUTION!
Do not use chemical flushes in your
transmission as the chemicals can damage
your transmission components. Such damage
is not covered by the New Vehicle Limited
Warranty.
CAUTION!

If a transmission fluid leak occurs, visit an
authorized dealer immediately. Severe
transmission damage may occur. An authorized
dealer has the proper tools to adjust the fluid
level accurately.

21_DPF_OM_EN_USC_t.book Page 388

SERVICING AND MAINTENANCE389
7. Remove the dipstick again and note the
fluid level on both sides. The fluid level
reading is only valid if there is a solid
coating of oil on both sides of the dipstick.
Note that the holes in the dipstick will be full
of fluid if the actual level is at or above the
hole. The fluid level should be between the
“HOT” (upper) reference holes on the
dipstick at normal operating temperature.
If the fluid level is low, add fluid through the
dipstick tube to bring it to the proper level.
Do not overfill. Use ONLY the specified fluid
Ú page 444. After adding any quantity of oil
through the dipstick tube, wait a minimum
of two minutes for the oil to fully drain into
the transmission before rechecking the
fluid level.
NOTE:

If it is necessary to check the transmission below
the operating temperature, the fluid level should be
between the two “COLD” (lower) holes on the
dipstick with the fluid at 60-70°F / 16-21°C. Only
use the COLD region of the dipstick as a rough refer -
ence when setting the fluid level after a transmis -sion service or fluid change. Re-check the fluid level,
and adjust as required, once the transmission
reaches normal operating temperature.

8. Reinsert the dipstick. Check for leaks.
Release the parking brake.
NOTE:

If it is necessary to check the transmission below
the operating temperature, the fluid level should be
between the two COLD (lower) holes on the dipstick
with the fluid at 68-86°F / 20-30°C. Only use the
COLD region of the dipstick as a rough reference
when setting the fluid level after a transmission
service or fluid change. Re-check the fluid level, and
adjust as required, once the transmission reaches
normal operating temperature.

Fluid And Filter Changes — Eight-Speed
Transmission
Under normal operating conditions, the fluid
installed at the factory will provide satisfactory
lubrication for the life of the vehicle.

Routine fluid and filter changes are not required.
However, change the fluid and filter if the fluid
becomes contaminated (with water, etc.), or if the
transmission is disassembled for any reason.

Fluid And Filter Changes — Six Speed
Transmission
For the proper maintenance intervals
Ú page 354.
In addition, change the fluid and filters if the
fluid becomes contaminated (with water, etc.),
or if the transmission is disassembled for any
reason.
CAUTION!
If the fluid temperature is below 50°F (10°C)
it may not register on the dipstick. Do not add
fluid until the temperature is elevated enough
to produce an accurate reading. Run the
engine at idle, in PARK, to warm the fluid.
CAUTION!
If the fluid temperature is below 50°F (10°C)
it may not register on the dipstick. Do not add
fluid until the temperature is elevated enough
to produce an accurate reading. Run the
engine at idle, in PARK, to warm the fluid.
8

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392SERVICING AND MAINTENANCE
Air Cleaner Assembly
Inspect air cleaner housing for proper assembly
and fit. Make certain that the air cleaner is
properly positioned and that the cover is tight.
Check all hoses leading to the air cleaner for
tightness. The air filter element must also be
clean and serviced according to the instructions
outlined in the Scheduled Maintenance section
of this manual.
Tampering With Noise Control System
Prohibited

Federal law prohibits the following acts or the
causing thereof: (1) the removal or rendering
inoperative by any person, other than for purposes
of maintenance, repair, or replacement, of any
device or element of design incorporated into any
new vehicle for the purpose of noise control prior to
its sale or delivery to the ultimate purchaser or while
it is in use, or (2) the use of the vehicle after such
device or element of design has been removed or
rendered inoperative by any person.

Among those acts presumed to constitute
tampering are the acts listed below. AIR CLEANER

Removal of the air cleaner.
Removal of the air cleaner filter element from
the air cleaner housing.
Removal of the air ducting.
EXHAUST SYSTEM
Removal or rendering inoperative exhaust
system components including the muffler or
tailpipe.
ENGINE COOLING SYSTEM
Removal or rendering inoperative the fan
clutch.
Removal of the fan shroud.
Noise Emission Warranty
The manufacturer warrants that this vehicle as
manufactured by the manufacturer, was
designed, built and equipped to conform at the
time it left the manufacturer's control with all
applicable U.S. EPA Noise Control Regulations.
This warranty covers this vehicle as designed,
built and equipped by the manufacturer, and is
not limited to any particular part, component or
system of the vehicle manufactured by the
manufacturer. Defects in design, assembly or in
any part, component or system of the vehicle as
manufactured by the manufacturer, which, at
the time it left the manufacturer's control,
caused noise emissions to exceed Federal
standards, are covered by this warranty for the
life of the vehicle.

21_DPF_OM_EN_USC_t.book Page 392

394SERVICING AND MAINTENANCE
(Continued)
FUSES
General Information The fuses protect electrical systems against
excessive current.
When a device does not work, you must check
the fuse element inside the blade fuse for a
break/melt.
Also, please be aware that when using power
outlets for extended periods of time with the
engine off may result in vehicle battery
discharge.
Blade Fuses

PERFORMED BY
PERFORMED AT
Noise Systems Maintenance Chart and Service Log — Insert Month, Day, Year under column mileage closest to the mileage at which
service was performed.
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.
WARNING! (Continued)
1 — Fuse Element
2 — Blade Fuse with a good/functional fuse
element
3 — Blade fuse with a bad/not functional fuse
element (blown fuse)

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450
INDEX
 Pair (Link) Uconnect Phone To A Mobile
Phone............................................................ 260 WARRANTY INFORMATION...................... 447
A
Adaptive Cruise Control (ACC)
(Cruise Control)
.................................... 164, 166Adding Engine Coolant (Antifreeze)............... 384Adding Fuel.................................................... 196Additives, Fuel............................................... 434Adjust Down........................................................... 35Forward....................................................... 35Rearward..................................................... 35Up................................................................ 35Adjustable Pedals............................................ 40Advance Phone Connectivity......................... 266Air BagAir Bag Operation...................................... 305Air Bag Warning Light................................ 303Enhanced Accident Response......... 310, 352Event Data Recorder (EDR)....................... 352If Deployment Occurs................................ 309Knee Impact Bolsters................................ 305Maintaining Your Air Bag System.............. 311Maintenance............................................. 311
Redundant Air Bag Warning Light............. 303Transporting Pets..................................... 330Air Bag Light................................ 107, 303, 331Air Cleaner, Engine (Engine Air Cleaner
Filter)................................................... 369, 391Air Conditioner Maintenance........................ 371Air Conditioner Refrigerant.................. 371, 372Air Conditioner System................................. 371Air Conditioning................................................ 62Air Conditioning Filter....................................... 65Air Conditioning System................................... 64Air Conditioning, Operating Tips....................... 65Air Filter........................................................ 369Air PressureTires......................................................... 415AlarmSecurity Alarm....................................23, 108Alterations/ModificationsVehicle......................................................... 10Antifreeze (Engine Coolant).......................... 384Capacities................................................. 439Disposal................................................... 385Anti-Lock Brake System (ABS)...................... 273Anti-Lock Warning Light................................ 113Assist, Hill Start............................................. 280Audio Settings............................................... 253Audio Systems (Radio).................................. 220
Auto Down Power Windows..............................77Automatic Door Locks......................................28Automatic Headlights.......................................52Automatic Temperature Control (ATC)..............64Automatic Transmission....................... 141, 389Adding Fluid.............................................. 389Fluid And Filter Change............................. 389Fluid Change............................................. 389Fluid Level Check............................. 387, 388Fluid Type........................................ 390, 444Shifting..................................................... 146Special Additives...................................... 387Automatic Transmission Limp Home Mode... 145AutoPark....................................................... 120AUX Camera......................................... 188, 194Auxiliary Driving Systems.............................. 281Axle Fluid.....................................390, 391, 444Axle Lubrication................................... 390, 391
B
Back-Up......................................................... 186Back-Up Camera........................................... 186Battery................................................. 108, 366Blanket..................................................... 130Charging System Light.............................. 108Keyless Key Fob Replacement....................16Battery Saver Feature......................................54

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451
Belts, Seat
..................................................... 330Bluetooth Connecting To A Particular Mobile Phone Or Audio Device After Pairing
................262Body Builders Guide........................................ 10Body Mechanism Lubrication........................ 380B-Pillar Location............................................. 411Brake Assist System...................................... 274Brake Control System.................................... 274Brake Fluid.......................................... 387, 444Brake System...................................... 387, 431Fluid Check............................................... 387Master Cylinder......................................... 387Parking...................................................... 137Warning Light............................................ 107Brake/Transmission Interlock....................... 141Bulb Replacement......................................... 401Bulbs, Light.......................................... 332, 401
C
Cab Top Clearance Lights.............................. 405Camera.......................................................... 186Camera, AUX........................................ 188, 194Camera, Rear...................................... 186, 189Capacities, Antifreeze (Engine Coolant)......... 439Capacities, Fluid............................................ 439Caps, FillerOil (Engine)................................................ 364Power Steering.......................................... 163Radiator (Coolant Pressure)...................... 385
Car Washes................................................... 428Carbon Monoxide Warning............................ 333Cargo Light....................................................... 54CD................................................................. 255Cellular Phone.............................................. 269Center High Mounted Stop Light................... 405Center Seat Storage Compartment.................. 67Changing A Flat Tire...................................... 339Charge Air Cooler.......................................... 386Chart, Tire Sizing........................................... 407Check Engine Light (Malfunction
Indicator Light).............................................. 117Checking Your Vehicle For Safety................. 330Checks, Safety.............................................. 330Child Restraint.............................................. 312Child RestraintsBooster Seats........................................... 315Child Seat Installation..................... 323, 325How To Stow An unused ALR Seat Belt.... 322Infant And Child Restraints....................... 313Locating The LATCH Anchorages.............. 320Lower Anchors And Tethers For Children.. 317Older Children And Child Restraints......... 314Seating Positions...................................... 316Clean Air Gasoline......................................... 433CleaningWheels..................................................... 421Climate Control................................................ 58Automatic.................................................... 59Manual........................................................ 62
Cold Weather Operation................................ 122Compact Spare Tire...................................... 419Contract, Service........................................... 446Controls........................................................ 247Cooling Pressure Cap (Radiator Cap)............ 385Cooling System............................................. 383Adding Coolant (Antifreeze)...................... 384Coolant Level................................... 384, 386Cooling Capacity....................................... 439Disposal Of Used Coolant......................... 385Drain, Flush, And Refill............................. 384Inspection................................................. 386Points To Remember................................ 386Pressure Cap............................................ 385Radiator Cap............................................. 385Selection Of Coolant (Antifreeze)..... 384, 440Corrosion Protection..................................... 427Cruise Control (Speed Control)............. 164, 166Cruise Light................................................... 115Customer Assistance.................................... 445Cybersecurity................................................ 220
D
Daytime Running Lights...................................51Dealer Service............................................... 367Defroster, Rear Window...................................62Defroster, Windshield............................ 62, 331Delay (Intermittent) Wipers..............................57Deleting A Phone........................................... 262Diagnostic System, Onboard......................... 116
11

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453
Fluid Level Checks Brake
........................................................ 387Power Steering.......................................... 163Fog Lights............................................... 53, 404Fold Flat Load Floor......................................... 70Fold-Flat Seats................................................. 33Forward Collision Warning............................. 281Four Wheel Drive........................................... 153Four-Way Hazard Flasher............................... 334Freeing A Stuck Vehicle................................. 349Front Axle (Differential).................................. 390Fuel............................................ 196, 433, 436Adding....................................................... 195Additives................................................... 434Clean Air.................................................... 433Diesel.............................................. 196, 436Ethanol...................................................... 434Filler Cap (Gas Cap)................................... 196Filter................................................ 375, 440Gasoline.................................................... 433Light.......................................................... 111Materials Added........................................ 434Methanol................................................... 434Octane Rating........................................... 433Requirements................................. 433, 436Specifications............................................ 436Tank Capacity............................................ 439Fuses............................................................. 394
G
Garage Door Opener (HomeLink)..................... 47Gas Cap (Fuel Filler Cap).............................. 196Gasoline, Clean Air........................................ 433Gasoline, Reformulated................................ 433GaugesVoltage..................................................... 128Gear Ranges................................................. 147Gear Selector Override................................. 347Glass Cleaning.............................................. 430Gross Axle Weight Rating.............................. 201Gross Vehicle Weight Rating......................... 201GuideBody Builders.............................................. 10GVWR............................................................ 199
H
HazardDriving Through Flowing, Rising, Or Shallow Standing Water
.................................... 218Hazard Warning Flashers.............................. 334Head Restraints............................................... 38Head Rests...................................................... 38Headlights.................................................... 402Automatic High Beam.................................. 52Cleaning................................................... 427High Beam................................................... 51Lights On Reminder..................................... 53Passing........................................................ 52Switch.......................................................... 50
Heated Mirrors.................................................46Heated Seats...................................................37Hill Descent Control...................................... 278Hill Descent Control Indicator....................... 278Hill Start Assist.............................................. 280HitchesTrailer Towing........................................... 204HomeLink (Garage Door Opener).....................47Hood Prop........................................................79Hood Release...................................................79Hub Caps...................................................... 343
I
Idle-Up Feature............................................. 132Ignition.............................................................18Switch..........................................................18Illuminated Entry..............................................56Inside Rearview Mirror.................... 41, 42, 335Instrument Cluster...................... 85, 86, 88, 89Descriptions.............................................. 115Display.........................................................90Engine Oil Reset..........................................91Instrument Panel Lens Cleaning................... 429Integrated Trailer Brake Control.................... 207Interior Appearance Care.............................. 428Interior Lights...................................................55Intermittent Wipers (Delay Wipers)..................57Intervention Regeneration Strategy..... 101, 379Inverter Outlet (115V)......................................74
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