2018 Ram 2500 AC repair

WARNING LIGHTS AND MESSAGES
Red Warning Lights
— Seat Belt Reminder Warning Light
This light indicates when the driver or pas-
senger seat belt is unbuckled. When the
ignition is first placed in the ON/RUN or
ACC/ON/RUN position and if the driver’s seat
belt is unbuckled, a chime will sound and the
light will turn on. When driving, if the driver
or front passenger seat belt remains unbuck-
led, the Seat Belt Reminder Light will flash or
remain on continuously and a chime will
sound. Refer to “Occupant Restraints Sys-
tems” in “Safety” for further information.
— Air Bag Warning Light
This light indicates a fault with the air bag,
and will turn on for four to eight seconds as a
bulb check when the ignition is placed in the
ON/RUN or ACC/ON/RUN position. This light
will illuminate with a single chime when a
fault with the air bag has been detected, it
will stay on until the fault is cleared. If thelight is either not on during startup, stays on,
or turns on while driving, have the system
inspected at an authorized dealer as soon as
possible.
— Brake Warning Light
This light monitors various brake functions,
including brake fluid level and parking brake
application. If the brake light turns on it may
indicate that the parking brake is applied,
that the brake fluid level is low, or that there
is a problem with the anti-lock brake system
reservoir.
If the light remains on when the parking brake
has been disengaged, and the fluid level is at
the full mark on the master cylinder reservoir, it
indicates a possible brake hydraulic system
malfunction or that a problem with the Brake
Booster has been detected by the Anti-Lock
Brake System (ABS) / Electronic Stability Con-
trol (ESC) system. In this case, the light will
remain on until the condition has been cor-
rected. If the problem is related to the brake
booster, the ABS pump will run when applying
the brake, and a brake pedal pulsation may be
felt during each stop.
The dual brake system provides a reserve
braking capacity in the event of a failure to a
portion of the hydraulic system. A leak in
either half of the dual brake system is indi-
cated by the Brake Warning Light, which will
turn on when the brake fluid level in the
master cylinder has dropped below a speci-
fied level.
The light will remain on until the cause is
corrected.
NOTE:
The light may flash momentarily during sharp
cornering maneuvers, which change fluid level
conditions. The vehicle should have service
performed, and the brake fluid level checked.
If brake failure is indicated, immediate repair
is necessary.
WARNING!
Driving a vehicle with the red brake light
on is dangerous. Part of the brake system
may have failed. It will take longer to stop
the vehicle. You could have a collision.
Have the vehicle checked immediately.
GETTING TO KNOW YOUR INSTRUMENT PANEL
76

Vehicles equipped with the Anti-Lock Brake
System (ABS) are also equipped with Elec-
tronic Brake Force Distribution (EBD). In the
event of an EBD failure, the Brake Warning
Light will turn on along with the ABS Light.
Immediate repair to the ABS system is re-
quired.
Operation of the Brake Warning Light can be
checked by turning the ignition switch from
the OFF position to the ON/RUN position.
The light should illuminate for approximately
two seconds. The light should then turn off
unless the parking brake is applied or a brake
fault is detected. If the light does not illumi-
nate, have the light inspected by your autho-
rized dealer.
The light also will turn on when the parking
brake is applied with the ignition switch in
the ON/RUN position.
NOTE:
This light shows only that the parking brake is
applied. It does not show the degree of brake
application.— Vehicle Security Warning Light — If
Equipped
This light will flash at a fast rate for approxi-
mately 15 seconds when the vehicle security
alarm is arming, and then will flash slowly
until the vehicle is disarmed.
— Engine Coolant Temperature Warn-
ing Light
This light warns of an overheated engine
condition. If the engine coolant temperature
is too high, this indicator will illuminate and a
single chime will sound. If the temperature
reaches the upper limit, a continuous chime
will be sound for four minutes or until the
engine is able to cool: whichever comes first.
If the light turns on while driving, safely pull
over and stop the vehicle. If the A/C system is
on, turn it off. Also, shift the transmission
into NEUTRAL and idle the vehicle. If the
temperature reading does not return to nor-
mal, turn the engine off immediately and call
for service. Refer to “If Your Engine Over-
heats” in “In Case Of Emergency” for further
information.
— Battery Charge Warning Light
This light illuminates when the battery is not
charging properly. If it stays on while the
engine is running, there may be a malfunc-
tion with the charging system. Contact your
authorized dealer as soon as possible.
This indicates a possible problem with the
electrical system or a related component.
— Oil Pressure Warning Light
This light indicates low engine oil pressure. If
the light turns on while driving, stop the
vehicle and shut off the engine as soon as
possible. A chime will sound when this light
turns on.
Do not operate the vehicle until the cause is
corrected. This light does not indicate how
much oil is in the engine. The engine oil level
must be checked under the hood.
— Electronic Throttle Control (ETC)
Warning Light
This light informs you of a problem with the
Electronic Throttle Control (ETC) system. If a
problem is detected while the vehicle is run-
ning, the light will either stay on or flash
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Should one or more tires be in the condition
mentioned above, the display will show the
indications corresponding to each tire in
sequence.
CAUTION!
Do not continue driving with one or more
flat tires as handling may be compro-
mised. Stop the vehicle, avoiding sharp
braking and steering. If a tire puncture
occurs, repair immediately using the dedi-
cated tire repair kit and contact your au-
thorized dealer as soon as possible.
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recom-
mended by the vehicle manufacturer on the
vehicle placard or tire inflation pressure la-
bel. (If your vehicle has tires of a different
size than the size indicated on the vehicle
placard or tire inflation pressure label, you
should determine the proper tire inflation
pressure for those tires.) As an added safety feature, your vehicle has
been equipped with a tire pressure monitor-
ing system (TPMS) that illuminates a low tire
pressure telltale when one or more of your
tires is significantly under-inflated. Accord-
ingly, when the low tire pressure telltale illu-
minates, you should stop and check your tires
as soon as possible, and inflate them to the
proper pressure. Driving on a significantly
under-inflated tire causes the tire to overheat
and can lead to tire failure. Under-inflation
also reduces fuel efficiency and tire tread
life, and may affect the vehicle’s handling
and stopping ability.
Please note that the TPMS is not a substitute
for proper tire maintenance, and it is the
driver’s responsibility to maintain correct tire
pressure, even if under-inflation has not
reached the level to trigger illumination of the
TPMS low tire pressure telltale.
Your vehicle has also been equipped with a
TPMS malfunction indicator to indicate when
the system is not operating properly. The
TPMS malfunction indicator is combined
with the low tire pressure telltale. When the
system detects a malfunction, the telltale will flash for approximately one minute and then
remain continuously illuminated. This se-
quence will continue upon subsequent ve-
hicle start-ups as long as the malfunction
exists. When the malfunction indicator is
illuminated, the system may not be able to
detect or signal low tire pressure as intended.
TPMS malfunctions may occur for a variety of
reasons, including the installation of replace-
ment or alternate tires or wheels on the ve-
hicle that prevent the TPMS from functioning
properly. Always check the TPMS malfunc-
tion telltale after replacing one or more tires
or wheels on your vehicle to ensure that the
replacement or alternate tires and wheels
allow the TPMS to continue to function
properly.
CAUTION!
The TPMS has been optimized for the
original equipment tires and wheels.
TPMS pressures and warning have been
established for the tire size equipped on
your vehicle. Undesirable system opera-
tion or sensor damage may result when
using replacement equipment that is not
GETTING TO KNOW YOUR INSTRUMENT PANEL
80

– 4WD AUTO Indicator Light — If
Equipped
This light alerts the driver that the vehicle is
in the four-wheel drive auto mode, and the
front axle is engaged, but the vehicle's power
is sent to the rear wheels. Four-wheel drive
will be automatically engaged when the ve-
hicle senses a loss of traction.
For further information on four-wheel drive
operation and proper use, refer to “Four-
Wheel Drive Operation — If Equipped” in
“Starting And Operating.”
White Indicator Lights
— Cruise Control Ready Indicator
This light will turn on when the speed control
is ready, but not set.
— Speed Control SET Indicator Light
— If Equipped
This light will turn on when the speed control
is set. Refer to “Speed Control — If
Equipped” in “Starting And Operating” for
further information.
— Hill Descent Control (HDC) Indicator
Light — If Equipped
This indicator shows when the Hill Descent
Control (HDC) feature is turned on. The lamp
will be on solid when HDC is armed. HDC can
only be armed when the transfer case is in the
“4WD LOW” position and the vehicle speed
is less then 30 mph (48 km/h). If these
conditions are not met while attempting to
use the HDC feature, the HDC indicator light
will flash on/off.
Blue Indicator Lights
— High Beam Indicator Light
This indicator shows that the high beam
headlights are on. With the low beams acti-
vated, push the multifunction lever forward
(toward the front of the vehicle) to turn on the
high beams. Pull the multifunction lever rear-
ward (toward the rear of the vehicle) to turn
off the high beams. If the high beams are off,
pull the lever toward you for a temporary high
beam on, "flash to pass" scenario.
ONBOARD DIAGNOSTIC SYSTEM —
OBD II
Your vehicle is equipped with a sophisticated
Onboard Diagnostic system called OBD II.
This system monitors the performance of the
emissions, engine, and transmission control
systems. When these systems are operating
properly, your vehicle will provide excellent
performance and fuel economy, as well as
engine emissions well within current govern-
ment regulations.
If any of these systems require service, the
OBD II system will turn on the Malfunction
Indicator Light (MIL). It will also store diag-
nostic codes and other information to assist
your service technician in making repairs.
Although your vehicle will usually be drivable
and not need towing, see your authorized
dealer for service as soon as possible.
CAUTION!
• Prolonged driving with the MIL on could
cause further damage to the emission
control system. It could also affect fuelGETTING TO KNOW YOUR INSTRUMENT PANEL
84

tion, the graphic in the instrument cluster
will still display a pressure value in a differ-
ent color.
• After driving the vehicle for up to 20 min- utes above 15 mph (24 km/h), the TPM
Telltale Light will flash on and off for
75 seconds and then remain on solid. In
addition, the instrument cluster will display
a "SERVICE TPM SYSTEM" message for a
minimum of five seconds and then display
dashes (- -) in place of the pressure value.
• For each subsequent ignition switch cycle, a chime will sound, the TPM Telltale Light
will flash on and off for 75 seconds and
then remain on solid, and the instrument
cluster will display a "SERVICE TPM SYS-
TEM" message for a minimum of five sec-
onds and then display dashes (- -) in place
of the pressure value.
•
Once you repair or replace the original road
tire and reinstall it on the vehicle in place of
the non matching full size spare or compact
spare, the TPMS will update automatically.
In addition, the TPM Telltale Light will turn
OFF and the graphic in the instrument clus-
ter will display a new pressure value instead
of dashes (- -), as long as no tire pressure is below the low-pressure warning limit in any
of the four active road tires. The vehicle may
need to be driven for up to 20 minutes above
15 mph (24 km/h) in order for the TPMS to
receive this information.
Tire Pressure Information System (TPIS)
3500 Series Trucks
Your vehicle may be equipped with a Tire
Pressure Information System (TPIS).
The Tire Pressure Information System (TPIS)
uses wireless technology with wheel rim
mounted electronic sensors to transmit tire
pressure levels. Sensors mounted to each
wheel as part of the valve stem transmit tire
pressure readings to the receiver module.
NOTE:
It is particularly important for you to check
the tire pressure in all of the tires on your
vehicle monthly and to maintain the proper
pressure.
The TPIS consists of the following compo-
nents:
• Receiver module
• Four TPM sensors (Single Rear Wheel
(SRW) applications)
• Six TPM sensors (Dual Rear Wheel (DRW) applications)
• Pressure display in the instrument cluster
The TPIS system will display all four (Single
Rear Wheel (SRW) applications) or six (Dual
Rear Wheel (DRW) applications) tire pressure
values in the instrument cluster display.
If a system fault is detected, the instrument
cluster will display a "SERVICE TPM SYS-
TEM" message for a minimum of five seconds
and then display dashes (- -) in place of the
pressure value to indicate which sensor is not
being received.
If the ignition switch is cycled, this sequence
will repeat, providing the system fault still
exists. If the system fault no longer exists, the
"SERVICE TPM SYSTEM" message will no
longer be displayed, and a pressure value will
display in place of the dashes. A system fault
can occur due to any of the following:
•
Signal interference due to electronic devices
or driving next to facilities emitting the same
radio frequencies as the TPM sensors.
SAFETY
92

have skin or eye irritation, rinse the area
with cool water. For nose or throat irritation,
move to fresh air. If the irritation continues,
see your doctor. If these particles settle on
your clothing, follow the garment manufac-
turer’s instructions for cleaning.
Do not drive your vehicle after the air bags
have deployed. If you are involved in another
collision, the air bags will not be in place to
protect you.
WARNING!
Deployed air bags and seat belt preten-
sioners cannot protect you in another col-
lision. Have the air bags, seat belt preten-
sioners, and the seat belt retractor
assemblies replaced by an authorized
dealer immediately. Also, have the Occu-
pant Restraint Controller System serviced
as well.
NOTE:
• Air bag covers may not be obvious in the interior trim, but they will open during air
bag deployment. • After any collision, the vehicle should be
taken to an authorized dealer immediately.
Enhanced Accident Response System
In the event of an impact, if the communica-
tion network remains intact, and the power
remains intact, depending on the nature of
the event, the ORC will determine whether to
have the Enhanced Accident Response Sys-
tem perform the following functions:
• Cut off fuel to the engine.
• Flash hazard lights as long as the batteryhas power or until the hazard light button is
pressed. The hazard lights can be deacti-
vated by pressing the hazard light button.
• Turn on the interior lights, which remain on as long as the battery has power.
• Unlock the power door locks.
Enhanced Accident Response System Reset
Procedure
In order to reset the Enhanced Accident Re-
sponse System functions after an event, the
ignition switch must be changed from igni-
tion START or ON/RUN to ignition OFF. Care-
fully check the vehicle for fuel leaks in the engine compartment and on the ground near
the engine compartment and fuel tank before
resetting the system and starting the engine.
Maintaining Your Air Bag System
WARNING!
• Modifications to any part of the air bag
system could cause it to fail when you
need it. You could be injured if the air
bag system is not there to protect you.
Do not modify the components or wiring,
including adding any kind of badges or
stickers to the steering wheel hub trim
cover or the upper right side of the
instrument panel. Do not modify the
front bumper, vehicle body structure, or
add aftermarket side steps or running
boards.
• It is dangerous to try to repair any part of
the air bag system yourself. Be sure to
tell anyone who works on your vehicle
that it has an air bag system.
• Do not attempt to modify any part of your
air bag system. The air bag may inflate
accidentally or may not function prop-
SAFETY
114

To Stow The Flat Or Spare
NOTE:
RAM 1500 vehicles equipped with alumi-
num wheels cannot be stored under the ve-
hicle because the wheel retainer will not fit
through the wheel pilot hole. Secure the flat
tire in the bed of the truck. Have the flat tire
repaired or replaced immediately.
1. Turn the wheel so that the valve stem isdown. Slide the wheel retainer through
the center of the wheel and position it
properly across the wheel opening.
2. For convenience in checking the spare tire inflation, stow with the valve stem toward
the rear of the vehicle.
3. Attach the lug wrench to the extension tubes with the curved angle facing away
from the vehicle. Rotate the lug wrench
handle clockwise until the wheel is drawn
into place against the underside of the
vehicle. Continue to rotate until you feel
the winch mechanism slip, or click three
or four times. It cannot be overtightened.
Push against the tire several times to be
sure it is firmly in place.
WARNING!
• Do not attempt to change a tire on theside of the vehicle close to moving traf-
fic. Pull far enough off the road to avoid
the danger of being hit when operating
the jack or changing the wheel.
• Being under a jacked-up vehicle is dan-
gerous. The vehicle could slip off the
jack and fall on you. You could be
crushed. Never put any part of your body
under a vehicle that is on a jack.
• Never start or run the engine while the
vehicle is on a jack. If you need to get
under a raised vehicle, take it to your
authorized dealer where it can be raised
on a lift.
• The jack is designed to be used as a tool
for changing tires only. The jack should
not be used to lift the vehicle for service
purposes. The vehicle should be jacked
on a firm level surface only. Avoid ice or
slippery areas.
• Do not attempt to change a tire on the
side of the vehicle close to moving traf-
fic, pull far enough off the road to avoid
WARNING!
the danger of being hit when operating
the jack or changing the wheel.
• Carefully follow these tire changing
warnings to help prevent personal injury
or damage to your vehicle:• Always park on a firm, level surface
as far from the edge of the roadway
as possible before raising the ve-
hicle.
• Turn on the Hazard Warning flash-
ers.
• Block the wheel diagonally opposite
the wheel to be raised.
• Set the parking brake firmly and set
an automatic transmission in
PARK; a manual transmission in
REVERSE.
• Do not let anyone sit in the vehicle
when it is on a jack.
• Do not get under the vehicle when it
is on a jack.
• Only use the jack in the positions
indicated and for lifting this vehicle
during a tire change.
IN CASE OF EMERGENCY
214

WARNING!
• If working on or near a roadway, beextremely careful of motor traffic.
• To assure that spare tires, flat or
inflated, are securely stowed,
spares must be stowed with the
valve stem facing the ground.
• Raising the vehicle higher than nec-
essary can make the vehicle less
stable. It could slip off the jack and
hurt someone near it. Raise the ve-
hicle only enough to remove the
tire.
• To avoid the risk of forcing the ve-
hicle off the jack, do not fully
tighten the wheel bolts until the
vehicle has been lowered. Failure to
follow this warning may result in
personal injury.
• To avoid possible personal injury,
handle the wheel covers with care to
avoid contact with any sharp edges.
WARNING!
• A loose tire or jack thrown forward ina collision or hard stop could en-
danger the occupants of the ve-
hicle. Always stow the jack parts
and the spare tire in the places
provided.
• A loose tire thrown forward in a
collision or hard stop could injure
the occupants in the vehicle. Have
the deflated (flat) tire repaired or
replaced immediately.
CAUTION!
• Do not attempt to raise the vehicle byjacking on locations other than those
indicated in the Jacking Instructions for
this vehicle.
• Before raising the wheel off the ground,
make sure that the jack will not damage
surrounding truck parts and adjust the
jack position as required.
• Use a back and forth motion to remove
the hub cap. Do not use a twisting mo-
CAUTION!
tion when removing the hub cap, dam-
age to the hub cap; finish may occur.
• The rear hubcaps on the dual rear wheel
has two pry off notches. Make sure that
the hook of the jack handle driver is
located squarely in the cap notch before
attempting to pull off.
Reinstalling The Jack And Tools
1500 Series Trucks
1. Tighten the jack all the way down by turning the jack turn-screw clockwise un-
til the jack is snug.
215