2021 RAM CHASSIS CAB wheel

SERVICING AND MAINTENANCE397
F32– –Spare
F33 20 Amp Blue –Trans Control Module – If Equipped
F34 30 Amp Pink –Vehicle System Interface Module #2 – If Equipped
F35 30 Amp Pink –Sunroof – If Equipped
F36 30 Amp Pink –Electric Back Light – If Equipped
F37 30 Amp Pink –Diesel Frame / Fuel Heater #2– If Equipped
F38 30 Amp Pink –Integrated Trailer Brake Module – If Equipped
F39 – –Spare
F40 –10 Amp Red Ventilated Seats – If Equipped
F41 –10 Amp Red Active Grille Shutter / Active Air Dam – If Equipped
F42 –20 Amp Yellow Horn
F43 –15 Amp Blue Heated Steering Wheel – If Equipped
F44 –10 Amp Red Diagnostic Port
F46 –10 Amp Red Upfitters Relay Coil – If Equipped
F47 – –Spare
F48 – –Spare
F49 –10 Amp Red IP Cluster / CSG
F50 –20 Amp Yellow Air Suspension Control Module – If Equipped
F51 –10 Amp RedIgnition Node Module / Keyless Ignition Node Module, Radio Frequency
Hub Module / Electric Steering Column Lock - If Equipped
F52 –5 Amp Tan Battery Sensor
Cavity Cartridge Fuse Micro Fuse Description
8

21_DPF_OM_EN_USC_t.book Page 397

402SERVICING AND MAINTENANCE
Replacing Exterior Bulbs
Base Quad: Low Beam Headlamp, High Beam
Headlamp, Front Park And Turn — If Equipped
Low Beam
See below steps to replace:

1. Open the hood.

2. Disconnect and isolate the negative battery
cable. 3. Reach into the front wheel house ahead of
the front wheel, remove the fastener, and
lift the cover over the access hole in the
front of the wheel house splash shield.
Access to the rear of the lamp can be gained
through this access hole.

Splash Shield Access Cover

Front Position (LED Headlamps)
LED (Serviced at an authorized dealer)
Turn Signal (LED Reflector Headlamp) 7444NA
Front Side Marker (Headlamps) LED (Serviced at an authorized dealer)
Front Fog Lamps (Halogen Reflector Headlamp) H11LL
Front Fog Lamps (LED Headlamp) LED (Serviced at an authorized dealer)
Side Indicators (Front And Side View Mirror) LED (Serviced at an authorized dealer)
Center High Mounted Stop Lamp (CHMSL) 921
Cab Roof Marker Lamps 194NA
Box Off Tail Lamps – Stop/Turn/Tail/License Plate 1157
Box Off Tail Lamps – Back Up 1156
Exterior Bulbs
Bulb Name Bulb Number

21_DPF_OM_EN_USC_t.book Page 402

SERVICING AND MAINTENANCE403
4. Reach through the access hole of the wheel
house splash shield and disengage the bulb
access cover by rotating counterclockwise.

Bulb Access Cover

5. Disconnect the internal lamp wiring harness connector from the low beam bulb. 6. Rotate the bulb counterclockwise a quarter
turn to unlock the bulb from the lamp.
7. Pull the bulb straight out from the housing.
8. Reverse the procedure for installation of new bulb and covers.
High Beam
See below steps to replace:

1. Open the hood.

2. Disconnect and isolate the negative battery cable.

Bulb Access Cover

3. Look under the hood and behind the headlamp to find the high beam bulb
access cover. 4. Reach behind the headlamp and disengage
the access cover by rotating counter -
clockwise.
5. Disconnect the internal lamp wiring harness connector from the high beam bulb.
6. Rotate the bulb counterclockwise a quarter turn to unlock the bulb from the lamp.
7. Pull the bulb straight out from the housing.
8. Reverse the procedure for installation of new bulb and covers.
CAUTION!
Do not contaminate the bulb glass by
touching it with your fingers or by allowing it
to contact other oily surfaces. Shortened
bulb life will result.

Always use the correct bulb size and type for
replacement. An incorrect bulb size or type
may overheat and cause damage to the
lamp, the bulb socket, or the lamp wiring.

CAUTION!
Do not contaminate the bulb glass by
touching it with your fingers or by allowing it
to contact other oily surfaces. Shortened
bulb life will result.
Always use the correct bulb size and type
for replacement. An incorrect bulb size or
type may overheat and cause damage to
the lamp, the bulb socket, or the lamp
wiring.
8

21_DPF_OM_EN_USC_t.book Page 403

404SERVICING AND MAINTENANCE
Outer Park And Turn
See below steps to replace:

1. Open the hood.

2. Disconnect and isolate the negative battery
cable.
3. Reach into the front wheel house ahead of the front wheel, remove the fastener, and
lift the cover over the access hole in the
front of the wheel house splash shield.
Access to the rear of the lamp can be gained
through this access hole.

Splash Shield Access Cover
4. Reach through the access hole of the wheel
house splash shield and disengage the side
marker socket by rotating counterclockwise
a quarter turn.

Park And Turn Socket

5. Pull the socket and bulb straight out from the housing.
6. Separate the bulb from the socket without twisting.
7. Reverse the procedure for installation of new bulb and covers. Fog Lamps — If Equipped
Halogen
See below steps to replace:

1. Reach under and behind the front fascia/
bumper to access the back of the front fog
lamp housing.

2. Disconnect the fog lamp wiring harness connector from the fog lamp bulb.

Fog Lamp Bulb

3. Rotate the bulb counterclockwise a quarter turn to unlock the bulb from the housing.
4. Pull the bulb straight out from the housing.
5. Reverse the procedure to install the bulb and cover.

21_DPF_OM_EN_USC_t.book Page 404

416SERVICING AND MAINTENANCE
Radial Ply Tires
Tire Repair
If your tire becomes damaged, it may be
repaired if it meets the following criteria:
The tire has not been driven on when flat.
The damage is only on the tread section of
your tire (sidewall damage is not repairable).
The puncture is no greater than a ¼ of an
inch (6 mm).
Consult an authorized tire dealer for tire repairs
and additional information.

Damaged Run Flat tires, or Run Flat tires that have
experienced a loss of pressure should be replaced
immediately with another Run Flat tire of identical
size and service description (Load Index and Speed
Symbol). Replace the tire pressure sensor as well as
it is not designed to be reused.

Run Flat Tires — If Equipped
Run Flat tires allow you the capability to drive
50 miles (80 km) at 50 mph (80 km/h) after a
rapid loss of inflation pressure. This rapid loss
of inflation is referred to as the Run Flat mode.
A Run Flat mode occurs when the tire inflation
pressure is of/or below 14 psi (96 kPa). Once a
Run Flat tire reaches the Run Flat mode it has
limited driving capabilities and needs to be
replaced immediately. A Run Flat tire is not
repairable. When a Run Flat tire is changed
after driving with underinflated tire condition,
please replace the TPM sensor as it is not
designed to be reused when driven under Run
Flat mode 14 psi (96 kPa) condition.
NOTE:
TPM Sensor must be replaced after driving the
vehicle on a flat tire condition.
It is not recommended driving a vehicle loaded
at full capacity or to tow a trailer while a tire is in
the Run Flat mode.
See the tire pressure monitoring section for
more information.
Tire Spinning
When stuck in mud, sand, snow, or ice
conditions, do not spin your vehicle's wheels
above 30 mph (48 km/h) or for longer than
30 seconds continuously without stopping.WARNING!

Combining radial ply tires with other types of tires
on your vehicle will cause your vehicle to handle
poorly. The instability could cause a collision.
Always use radial ply tires in sets of four. Never
combine them with other types of tires.

WARNING!

Fast spinning tires can be dangerous. Forces
generated by excessive wheel speeds may
cause tire damage or failure. A tire could
explode and injure someone. Do not spin your
vehicle's wheels faster than 30 mph (48 km/h)
for more than 30 seconds continuously when
you are stuck, and do not let anyone near a
spinning wheel, no matter what the speed.

21_DPF_OM_EN_USC_t.book Page 416

SERVICING AND MAINTENANCE417
Tread Wear Indicators
Tread wear indicators are in the original
equipment tires to help you in determining
when your tires should be replaced.

Tire Tread

These indicators are molded into the bottom of
the tread grooves. They will appear as bands
when the tread depth becomes a 1/16 of an
inch (1.6 mm). When the tread is worn to the
tread wear indicators, the tire should be
replaced.
Life Of Tire
The service life of a tire is dependent upon
varying factors including, but not limited to:
Driving style.

Tire pressure - Improper cold tire inflation pres -
sures can cause uneven wear patterns to
develop across the tire tread. These abnormal
wear patterns will reduce tread life, resulting in
the need for earlier tire replacement.

Distance driven.
Performance tires, tires with a speed rating of
V or higher, and Summer tires typically have
a reduced tread life. Rotation of these tires
per the vehicle scheduled maintenance is
highly recommended. NOTE:
Wheel valve stem must be replaced as well
when installing new tires due to wear and tear
in existing tires.
Keep dismounted tires in a cool, dry place with
as little exposure to light as possible. Protect
tires from contact with oil, grease, and gasoline.
Replacement Tires

The tires on your new vehicle provide a balance of
many characteristics. They should be inspected
regularly for wear and correct cold tire inflation
pressures. The manufacturer strongly recommends
that you use tires equivalent to the originals in size,
quality and performance when replacement is
needed

Ú
page 417. Refer to the Tire and Loading
Information placard or the Vehicle Certification
Label for the size designation of your tire. The Load
Index and Speed Symbol for your tire will be found
on the original equipment tire sidewall.

For more information relating to the Load Index
and Speed Symbol of a tire Ú page 406.
It is recommended to replace the two front tires
or two rear tires as a pair. Replacing just one tire
can seriously affect your vehicle’s handling.
1 — Worn Tire
2 — New Tire
WARNING!
Tires and the spare tire should be replaced
after six years, regardless of the remaining
tread. Failure to follow this warning can result
in sudden tire failure. You could lose control
and have a collision resulting in serious injury
or death.
8

21_DPF_OM_EN_USC_t.book Page 417

418SERVICING AND MAINTENANCE
(Continued)
If you ever replace a wheel, make sure that the
wheel’s specifications match those of the
original wheels.
It is recommended you contact an authorized
tire dealer or original equipment dealer with any
questions you may have on tire specifications
or capability. Failure to use equivalent
replacement tires may adversely affect the
safety, handling, and ride of your vehicle.TIRE TYPES
All Season Tires — If Equipped
All Season tires provide traction for all seasons
(Spring, Summer, Autumn, and Winter). Traction
levels may vary between different all season
tires. All season tires can be identified by the
M+S, M&S, M/S or MS designation on the tire
sidewall. Use all season tires only in sets of four;
failure to do so may adversely affect the safety
and handling of your vehicle.
Summer Or Three Season Tires — If
Equipped
Summer tires provide traction in both wet and
dry conditions, and are not intended to be
driven in snow or on ice. If your vehicle is
equipped with Summer tires, be aware these
tires are not designed for Winter or cold driving
conditions. Install Winter tires on your vehicle
when ambient temperatures are less than 40°F
(5°C) or if roads are covered with ice or snow.
For more information, contact an authorized
dealer.
WARNING!
Do not use a tire, wheel size, load rating, or
speed rating other than that specified for
your vehicle. Some combinations of unap -
proved tires and wheels may change
suspension dimensions and performance
characteristics, resulting in changes to
steering, handling, and braking of your
vehicle. This can cause unpredictable
handling and stress to steering and
suspension components. You could lose
control and have a collision resulting in
serious injury or death. Use only the tire and
wheel sizes with load ratings approved for
your vehicle.
Never use a tire with a smaller load index or
capacity, other than what was originally
equipped on your vehicle. Using a tire with
a smaller load index could result in tire
overloading and failure. You could lose
control and have a collision.
Failure to equip your vehicle with tires
having adequate speed capability can
result in sudden tire failure and loss of
vehicle control.
CAUTION!
Replacing original tires with tires of a
different size may result in false speedometer
and odometer readings.
WARNING! (Continued)

21_DPF_OM_EN_USC_t.book Page 418

SERVICING AND MAINTENANCE419
Summer tires do not contain the all season
designation or mountain/snowflake symbol on
the tire sidewall. Use Summer tires only in sets
of four; failure to do so may adversely affect the
safety and handling of your vehicle.
Snow Tires
Some areas of the country require the use of
snow tires during the Winter. Snow tires can be
identified by a “mountain/snowflake” symbol
on the tire sidewall.
If you need snow tires, select tires
equivalent in size and type to the
original equipment tires. Use snow
tires only in sets of four; failure to do
so may adversely affect the safety and handling
of your vehicle. Snow tires generally have lower speed ratings
than what was originally equipped with your
vehicle and should not be operated at
sustained speeds over 75 mph (120 km/h).
For speeds above 75 mph (120 km/h) refer to
original equipment or an authorized tire dealer
for recommended safe operating speeds,
loading and cold tire inflation pressures.
While studded tires improve performance
on ice, skid and traction capability on wet or
dry surfaces may be poorer than that of
non-studded tires. Some states prohibit
studded tires; therefore, local laws should
be checked before using these tire types.SPARE TIRES — IF EQUIPPED
For restrictions when towing with a spare tire
designated for temporary emergency use
Ú
page 206.
Spare Tire Matching Original Equipped Tire
And Wheel — If Equipped
Your vehicle may be equipped with a spare tire
and wheel equivalent in look and function to the
original equipment tire and wheel found on the
front or rear axle of your vehicle. This spare tire
may be used in the tire rotation for your vehicle.
If your vehicle has this option, refer to an
authorized tire dealer for the recommended tire
rotation pattern.
Compact Spare Tire — If Equipped
The compact spare is for temporary emergency
use only. You can identify if your vehicle is
equipped with a compact spare by looking at
the spare tire description on the Tire and
Loading Information Placard located on the
driver’s side door opening or on the sidewall of
the tire. Compact spare tire descriptions begin
with the letter “T” or “S” preceding the size
designation. Example: T145/80D18 103M.
T, S = Temporary Spare Tire
Since this tire has limited tread life, the original
equipment tire should be repaired (or replaced)
and reinstalled on your vehicle at the first
opportunity.
WARNING!
Do not use Summer tires in snow/ice
conditions. You could lose vehicle control,
resulting in severe injury or death. Driving too
fast for conditions also creates the possibility
of loss of vehicle control.
CAUTION!
Because of the reduced ground clearance, do
not take your vehicle through an automatic
car wash with a compact or limited use
temporary spare installed. Damage to the
vehicle may result.8

21_DPF_OM_EN_USC_t.book Page 419