trailer RAM 1500 2021 Repair Manual

398SERVICING AND MAINTENANCE
If equipped with Stop/Start, replace
accessory drive belt with OEM grade
Mopar belt. X
Replace spark plugs.
1X
Flush and replace the engine coolant
at 10 years or 150,000 miles
(240,000 km) whichever comes first. X
X
Inspect the transfer case fluid, change
for any of the following: police, taxi,
fleet, or frequent trailer towing. X
X
Change the transfer case fluid. X
Inspect and replace PCV valve if
necessary. X
1. The spark plug change interval is mileage based only; yearly intervals do not apply.
Mileage or time passed (whichever
comes first)
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
110,000
120,000
130,000
140,000
150,000
Or Years: 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
32,000
48,000
64,000
80,000
96,000
112,000
128,000
144,000
160,000
176,000
192,000
208,000
224,000
240,000

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SERVICING AND MAINTENANCE399
SCHEDULED SERVICING — DIESEL ENGINE
Your vehicle is equipped with an automatic oil
change indicator system. The oil change
indicator system will remind you that it is time to
take your vehicle in for scheduled maintenance. Based on engine operation conditions, the oil
change indicator message will illuminate. This
means that service is required for your vehicle.
Operating conditions such as frequent
short-trips, trailer tow, extremely hot or cold
ambient temperatures will influence when the
“Oil Change Required” message is displayed.
Severe Operating Conditions will cause the
change oil message to illuminate more
frequently. Have your vehicle serviced as soon
as possible, within the next 500 miles
(805 km).
An authorized dealer will reset the oil change
indicator message after completing the
scheduled oil change. If a scheduled oil change
is performed by someone other than an
authorized dealer, the message can be reset by
referring to the steps described under
Instrument Cluster Display Ú
page 114.NOTE:
Under no circumstances should oil change
intervals exceed 10,000 miles (16,000 km) or
12 months, whichever comes first.
Once A Month Or Before A Long Trip:
Check engine oil level
Check windshield washer fluid level
Check the tire inflation pressures and look
for unusual wear or damage
Check the fluid levels of the coolant reservoir,
brake master cylinder, and power steering,
and fill as needed
Check function of all interior and exterior
lights
WARNING!
You can be badly injured working on or
around a motor vehicle. Do only service
work for which you have the knowledge and
the right equipment. If you have any doubt
about your ability to perform a service job,
take your vehicle to a competent mechanic.
Failure to properly inspect and maintain
your vehicle could result in a component
malfunction and effect vehicle handling
and performance. This could cause an acci
-
dent.
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SERVICING AND MAINTENANCE401
Mileage or time passed (whichever comes first)
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
110,000
120,000
130,000
140,000
150,000
Or Years: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
16,000
32,000
48,000
64,000
80,000
96,000
112,000
128,000
144,000
160,000
176,000
192,000
208,000
224,000
240,000
Additional Inspections
Completely fill the Diesel Exhaust Fluid tank. X X X X X X X X X X X X X X X
Inspect the CV/Universal joints. X X X X X X X X X X X X X X X
Inspect front suspension, tie rod ends, and replace if
necessary. X X X X X X X
Inspect the front and rear axle fluid. If gear oil leakage is
suspected, check the fluid level. If using your vehicle for
police, taxi, fleet, off-road or frequent trailer towing change
the axle fluid. X
XXXX
Inspect the brake linings, parking brake function. X X X X X X X
Additional Maintenance
Replace cabin air filter X X X X X X X
Drain water from fuel filter assembly. X X X X X X X X X X X X X X X
Replace fuel filter and drain water from the fuel filter
assembly.
1Fuel filter replacement intervals should be every second oil change and must not exceed 20,000 miles (32,000 km) if using diesel fuel up to B5.
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402SERVICING AND MAINTENANCE
Replace engine air cleaner. XXXXX
Flush and replace the engine coolant at 10 years or
150,000 miles (240,000 km) whichever comes first. X
X
Replace accessory drive belt(s). X
Inspect the transfer case fluid, change for any of the
following: police, taxi, fleet, or frequent trailer towing. X
X
Change transfer case fluid. X
1. Under normal conditions the diesel fuel filter should be replaced every 20,000 miles (32,000 km) (every other oil change). If the vehicle is being used in severe operating conditions,
or In certain geographical areas of the country (Pennsylvania, New York, Ohio, Maryland, West Virginia, Arkansas, Oklahoma, Kansas, Iowa, Missouri and Nebraska) due to fuel
cleanliness issues, it’s recommended to replace the fuel filter every 10,000 miles (16,000 km).
Mileage or time passed (whichever comes first)
10,000
20,000
30,000
40,000
50,000
60,000
70,000
80,000
90,000
100,000
110,000
120,000
130,000
140,000
150,000
Or Years: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Or Kilometers:
16,000
32,000
48,000
64,000
80,000
96,000
112,000
128,000
144,000
160,000
176,000
192,000
208,000
224,000
240,000

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SERVICING AND MAINTENANCE429
F06–10 Amp Red OUTPUT TO UPFITTER PDC — If Equipped
F07 ––Spare
F08 20 Amp Blue –Trailer Tow Backup
F09 –20 Amp Yellow Trailer Stop / Turn Lamp Left
F10 –20 Amp Yellow Trailer Stop / Turn Lamp Right
F11 –15 Amp Blue ID/CLEARANCE LIGHTS — If Equipped
F12 20 Amp Blue –Trailer Tow Park Lamp
F13 ––Spare
F14 –10 Amp Red AC Clutch
F15 –5 Amp Tan Intelligent Battery Sensor (IBS)
F16 ––Spare
F17 –20 Amp Yellow Air Suspension
F18 –15 Amp Blue AGS / Rear Axle Cooling Valve / Active Air Dam
F19 ––Spare
F20 –20 Amp Yellow Adjustable Pedals
F21 30 Amp Pink –Power Side Step
F22 50 Amp Red –Air Module
F23 ––Spare
F24 –20 Amp Yellow TCM SBW
F25 40 Amp Green –Exterior Lights 2
Cavity Cartridge Fuse Micro Fuse Description
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430SERVICING AND MAINTENANCE
F2650 Amp Red –ESP Module
F27 30 Amp Pink –Front Wiper
F28 –10 Amp Red PCM / ECM
F29 40 Amp Green –ESP Module
F30 ––Spare
F31 ––Spare
F32 20 Amp Blue –ECM / PCM
F33 30 Amp Pink –Brake Vacuum Pump
F34 ––Spare
F35 –10 Amp RedPCM / ECM / Power Pack Unit (PPU) Motor Generator Unit (MGU)
Wake Up / EPS / Active Tuned Mass Module (ATMM) / ESP
F36 ––Spare
F37 –5 Amp Tan R / S Output to iPDC
F38 –10 Amp Red DTCM / Active CL TEMP VLV
F39 –15 Amp Red MOD ATMM
F40 40 Amp Green –Starter
F41 –10 Amp Red IRCAM Heaters
F42 20 Amp Blue –AUX SWITCH #5 — If Equipped
F43 –20 Amp Yellow MGU Coolant Pump
F44 –10 Amp Red Trailer Camera
F45 –10 Amp Red ADCM — If Equipped
CavityCartridge Fuse Micro Fuse Description

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432SERVICING AND MAINTENANCE
Internal Power Distribution Center
The Power Distribution Center is located under
the drivers side instrument panel. This center
contains cartridge fuses, micro fuses, relays,
and circuit breakers. A description of each fuse
and component may be stamped on the inside
cover, otherwise the cavity number of each fuse
is stamped on the inside cover that corresponds
to the following chart.CAUTION!
When installing the power distribution
center cover, it is important to ensure the
cover is properly positioned and fully
latched. Failure to do so may allow water to
get into the power distribution center and
possibly result in an electrical system
failure.
When replacing a blown fuse, it is important
to use only a fuse having the correct
amperage rating. The use of a fuse with a
rating other than indicated may result in a
dangerous electrical system overload. If a
properly rated fuse continues to blow, it
indicates a problem in the circuit that must
be corrected.
CavityCartridge Fuse Micro Fuse Description
F0130 Amp Pink –Trailer Tow Receptacle
F03 –20 Amp Yellow Module Seat Heater Front (Pass)
F04 ––Spare
F05 –20 Amp Yellow Module PPU Cooling Fan
F06 ––Spare
F07 40 Amp Green –Mod CBC 3 PWR Locks
F08 ––Spare

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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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434SERVICING AND MAINTENANCE
F29–20 Amp Yellow Mod CRSM (Heat Rear LT)
F30 30 Amp Pink –Mod DTCM / Mod Tailgate
F31 30 Amp Pink –Mod CBC 1 Interior Light
F32 –20 Amp Yellow RT Spot Lamp — If Equipped
F33 –10 Amp RedAssy Overhead Console / Switch 911 / Switch Assist / Heads Up
Display (HUD)
F34 –15 Amp Blue Frt & RR Ventilated Seat Motor
F35 –10 Amp RedMod Inverter / Mtr Sunshade Sunroof / Mtr Dual Sunroof / USB
Charge Only
F36 40 Amp Green –Mod CBC 2 Exterior Light 1
F37 ––Spare
F38 ––Spare
F39 ––Spare
F40 20 Amp Blue –Dome Pursuit Vehicle — If Equipped
F41 A&B –15 Amp BlueLumbar Support & Pass SW / Mod ICS Sw Bank / HVAC Ctrl / Sw
Bank Upper / Mod Ctrl Steering
F42 A&B –10 Amp RedMod Transfer Case Switch Module (TCSM) / SBW / Electric Park
Brake SW / Overhead Console (OHC) SW / E-Call / Bank 3 SW / Seat
LT & RT Vent / Mod Trailer A&B Tire Pressure / Mod Gateway Trailer
F43 A&B –10 Amp Red Port Diagnostics / Mod CD / Front & Rear USB
F44 –20 Amp Yellow Radio / DCSD / Telematics Box Mod / Fleet Telematics Module
(FTM)
Cavity
Cartridge Fuse Micro Fuse Description

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SERVICING AND MAINTENANCE435
F4530 Amp Pink –Mod Door MUX Driver
F46 30 Amp Pink –Mod Door MUX Passenger
F47 A&B ––Spare
F48A -10 Amp RedRear View Mirror / SW Window Passenger / Rear USB / Wireless
Charging Pad Mod
F49 –15 Amp BlueMod CVPM / SNSR Blind Spot / HDLP Adaptive Front Lighting
Sensor (AFLS)
F50A –10 Amp Red Battery PACK Control Mod
F51 A&B ––Spare
F52 20 Amp Blue –Direct Battery Feed — If Equipped
F53 –10 Amp Red Trailer Reverse Steering Control / Trailer Steering Control Knob
F54B –20 Amp Yellow Power Outlet Center Seat
F55 25 Amp White –Upfitter — If Equipped
F56 30 Amp Pink –Mod Network Interface — If Equipped
F57 20 Amp Blue –Direct Battery Feed — If Equipped
F58 20 Amp Blue –Direct Battery Feed — If Equipped
F60 50 Amp Red –Mod Inverter
F61 ––Spare
F62 A&B –10 Amp RedITBM / Mod Occupant Class / Mod IAIR Suspension / Mod HVAC
Snsr Incar Temp / Rear Coolant Temp / PTS / Mod IRCM / HRLS /
Mod Gateway Trailer TPM
Cavity
Cartridge Fuse Micro Fuse Description
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