2017 JEEP GRAND CHEROKEE service

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 automatic transmis-
sion 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
government 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 couldcause further damage to the emission
control system. It could also affect fuel
economy and driveability. The vehicle
must be serviced before any emissions
tests can be performed.
• If the MIL is flashing while the engine is
running, severe catalytic converter dam-
age and power loss will soon occur. Im-
mediate service is required.
Onboard Diagnostic System (OBD II)
Cybersecurity
Your vehicle is required to have an Onboard
Diagnostic system (OBD II) and a connection
port to allow access to information related to
the performance of your emissions controls.
Authorized service technicians may need to
access this information to assist with the
diagnosis and service of your vehicle and
emissions system.
WARNING!
• ONLY an authorized service technicianshould connect equipment to the OBD II
connection port in order to diagnose or
service your vehicle.
• If unauthorized equipment is connected
to the OBD II connection port, such as a
driver-behavior tracking device, it may:• Be possible that vehicle systems,
including safety related systems,
could be impaired or a loss of ve-
hicle control could occur that may
result in an accident involving seri-
ous injury or death.
• Access, or allow others to access,
information stored in your vehicle
systems, including personal infor-
mation.
For further information, refer to “Privacy
Practices” and “Uconnect CyberSecurity” in
“All About Uconnect Access” in your Owner’s
Manual Radio Supplement and “Cybersecu-
rity” in “Multimedia” in your Owner's Manual
at www.jeep.com/en/owners/manuals/.
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SAFETY FEATURES
Anti-Lock Brake System (ABS)
The Anti-Lock Brake System (ABS) provides
increased vehicle stability and brake perfor-
mance under most braking conditions. The
system automatically prevents wheel lock,
and enhances vehicle control during braking.
The ABS performs a self-check cycle to en-
sure that the ABS is working properly each
time the vehicle is started and driven. During
this self-check, you may hear a slight clicking
sound as well as some related motor noises.
ABS is activated during braking when the
system detects one or more wheels begin to
lock. Road conditions such as ice, snow,
gravel, bumps, railroad tracks, loose debris,
or panic stops may increase the likelihood of
ABS activation(s).
You also may experience the following when
ABS activates:
• The ABS motor noise (it may continue torun for a short time after the stop).
• The clicking sound of solenoid valves.
• Brake pedal pulsations. • A slight drop of the brake pedal at the end
of the stop.
These are all normal characteristics of ABS.
WARNING!
• The ABS contains sophisticated elec- tronic equipment that may be suscep-
tible to interference caused by improp-
erly installed or high output radio
transmitting equipment. This interfer-
ence can cause possible loss of anti-lock
braking capability. Installation of such
equipment should be performed by
qualified professionals.
• Pumping of the Anti-Lock Brakes will
diminish their effectiveness and may
lead to a collision. Pumping makes the
stopping distance longer. Just press
firmly on your brake pedal when you
need to slow down or stop.
• The ABS cannot prevent the natural laws
of physics from acting on the vehicle,
nor can it increase braking or steering
efficiency beyond that afforded by the
WARNING!
condition of the vehicle brakes and tires
or the traction afforded.
• The ABS cannot prevent collisions, in-
cluding those resulting from excessive
speed in turns, following another vehicle
too closely, or hydroplaning.
• The capabilities of an ABS equipped
vehicle must never be exploited in a
reckless or dangerous manner that could
jeopardize the user’s safety or the safety
of others.
ABS is designed to function with the OEM
tires. Modification may result in degraded
ABS performance.
Anti-Lock Brake Warning Light
The yellow “Anti-Lock Brake Warning Light”
will turn on when the ignition is turned to the
ON/RUN mode and may stay on for as long as
four seconds.
If the “Anti-Lock Brake Warning Light” re-
mains on or comes on while driving, it indi-
cates that the anti-lock portion of the brake
system is not functioning and that service is
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required. However, the conventional brake
system will continue to operate normally if
the “Brake System Warning Light” is not on.
If the “Anti-Lock Brake Warning Light” is on,
the brake system should be serviced as soon
as possible to restore the benefits of anti-lock
brakes. If the “Anti-Lock Brake Warning
Light” does not come on when the ignition is
turned to the ON/RUN mode, have the light
repaired as soon as possible.
Electronic Brake Control System
Your vehicle is equipped with an advanced
Electronic Brake Control system (EBC). This
system includes Electronic Brake Force Dis-
tribution (EBD), Anti-Lock Brake System
(ABS), Brake Assist System (BAS), Hill Start
Assist (HSA), Traction Control System (TCS),
Electronic Stability Control (ESC), and Elec-
tronic Roll Mitigation (ERM). These systems
work together to enhance both vehicle stabil-
ity and control in various driving conditions.Your vehicle may also be equipped with
Trailer Sway Control (TSC), Ready Alert Brak-
ing (RAB), Rain Brake Support (RBS), Dy-
namic Steering Torque (DST), Hill Descent
Control (HDC), and Selec-Speed Control
(SSC).
Electronic Brake Force Distribution (EBD)
This function manages the distribution of the
braking torque between the front and rear
axles by limiting braking pressure to the rear
axle. This is done to prevent overslip of the
rear wheels to avoid vehicle instability, and to
prevent the rear axle from entering ABS be-
fore the front axle.
Brake System Warning Light
The red “Brake System Warning Light” will
turn on when the ignition is turned to the
ON/RUN mode and may stay on for as long as
four seconds.
If the “Brake System Warning Light” remains
on or comes on while driving, it indicates that
the brake system is not functioning properly
and that immediate service is required. If the“Brake System Warning Light” does not
come on when the ignition is turned to the
ON/RUN mode, have the light repaired as
soon as possible.
Brake Assist System (BAS)
The BAS is designed to optimize the vehicle’s
braking capability during emergency braking
maneuvers. The system detects an emer-
gency braking situation by sensing the rate
and amount of brake application and then
applies optimum pressure to the brakes. This
can help reduce braking distances. The BAS
complements the anti-lock brake system
(ABS). Applying the brakes very quickly re-
sults in the best BAS assistance. To receive
the benefit of the system, you must apply
continuous braking pressure during the stop-
ping sequence, (do not “pump” the brakes).
Do not reduce brake pedal pressure unless
braking is no longer desired. Once the brake
pedal is released, the BAS is deactivated.
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NOTE:
It is particularly important, for you to regu-
larly check the tire pressure in all of your tires
and to maintain the proper pressure.
The Tire Pressure Monitor System (TPMS)
consists of the following components:
• Receiver Module
• Four Tire Pressure Monitoring Sensors
• Various Tire Pressure Monitoring SystemMessages, which display in the instrument
cluster, and a graphic displaying tire pres-
sures
• Tire Pressure Monitoring Telltale Light
Tire Pressure Monitoring Low Pressure
Warnings
The Tire Pressure Monitor-
ing Telltale Light will illu-
minate in the instrument
cluster, and an audible
chime will be activated,
when one or more of the
four active road tire pressures are low. In
addition, the instrument cluster will display a
"Tire Low" message, an "Inflate to XXX" mes- sage and a graphic display of the pressure
value(s) with the low tire(s) displayed in a
different color. Refer to “Instrument Cluster
Display” in “Getting To Know Your Instru-
ment Panel” for further information.
NOTE:
Your system can be set to display pressure
units in PSI, BAR or kPa.
Should a low tire condition occur on any of
the four active road tire(s), you should stop as
soon as possible, and inflate the low tire(s)
that is in a different color on the graphic
display to the vehicle’s recommended cold
tire pressure displayed in the "Inflate to XXX"
message.
NOTE:
When filling warm tires, the tire pressure may
need to be increased up to an additional 4 psi
(30 kPa) above the recommended cold plac-
ard pressure in order to turn the Tire Pressure
Monitoring Telltale Light off. The system will
automatically update, the graphic display of
the pressure value(s) will return to its original
color and the Tire Pressure Monitoring Tell-
tale Light will extinguish once the updated
tire pressure(s) have been received. The ve-
hicle may need to be driven for up to 20 min-
utes above 15 mph (24 km/h) to receive this
information.Service TPM System Warning
The Tire Pressure Monitoring Telltale Light
will flash on and off for 75 seconds, and
remain on solid when a system fault is de-
tected. The system fault will also sound a
chime. The instrument cluster display will
display a “SERVICE TPM SYSTEM” message
for a minimum of five seconds. This message
Low Tire Pressure Monitor Display
109

is then followed by a graphic display, with “-
-“ in place of the pressure value(s), indicat-
ing which Tire Pressure Monitoring Sensor(s)
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
Tire Pressure Monitoring Telltale Light will no
longer flash, the "SERVICE TPM SYSTEM"
message will not be present, and a pressure
value will be displayed instead of dashes. A
system fault can occur by any of the follow-
ing:
• Jamming due to electronic devices or driv-ing next to facilities emitting the same
Radio Frequencies as the TPM sensors.
• Installing some form of aftermarket win- dow tinting that affects radio wave signals.
• Lots of snow or ice around the wheels or wheel housings.
• Using tire chains on the vehicle.
• Using wheels/tires not equipped with TPM sensors. NOTE:
There is no tire pressure monitoring sensor in
the spare tire. The TPMS will not be able to
monitor the tire pressure. If you install the
spare tire in place of a road tire that has a
pressure below the low-pressure warning
limit, upon the next ignition switch cycle, the
Tire Pressure Monitoring Telltale Light will
remain ON, a chime will sound, and the
instrument cluster display will still display a
pressure value in the different color graphic
display and an "Inflate to XXX kPa" message
will be displayed. After driving the vehicle for
up to 20 minutes above 15 mph (24 km/h),
the Tire Pressure Monitoring Telltale Light
will flash on and off for 75 seconds and then
remain on solid. In addition, the instrument
cluster display will display a “SERVICE TPM
SYSTEM" message for five seconds and then
display dashes (- -) in place of the pressure
value. For each subsequent ignition switch
cycle, a chime will sound, the Tire Pressure
Monitoring Telltale Light will flash on and off
for 75 seconds and then remain on solid, and
the instrument cluster display will display a
"SERVICE TPM SYSTEM" message for five
seconds 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 spare tire, the
TPMS will update automatically.
In addition, the Tire Pressure Monitoring Tell-
tale Light will turn OFF and the graphic in the
instrument cluster display 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 informa-
tion.
TPMS Deactivation — If Equipped
The TPMS can be deactivated if replacing all
four wheel and tire assemblies (road tires)
with wheel and tire assemblies that do not
have TPMS Sensors, such as when installing
winter wheel and tire assemblies on your
vehicle.
To deactivate the TPMS, first, replace all four
wheel and tire assemblies (road tires) with
tires not equipped with Tire Pressure Moni-
toring (TPM) Sensors. Then, drive the vehicle
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for 10 minutes above 15 mph (24 km/h). The
TPMS will chime, the "TPM Telltale Light"
will flash on and off for 75 seconds and then
remain on. The instrument cluster will dis-
play the “SERVICE TPM SYSTEM” message
and then display dashes (--) in place of the
pressure values.
Beginning with the next ignition cycle, the
TPMS will no longer chime or display the
“SERVICE TPM SYSTEM” message in the
instrument cluster but dashes (--) will remain
in place of the pressure values.
To reactivate the TPMS, replace all four
wheel and tire assemblies (road tires) with
tires equipped with TPM sensors. Then, drive
the vehicle for up to 10 minutes above
15 mph (24 km/h). The TPMS will chime, the
"TPM Telltale Light" will flash on and off for
75 seconds and then turn off. The instrument
cluster will display the “SERVICE TPM SYS-
TEM” message and then display pressure
values in place of the dashes. On the next
ignition cycle the "SERVICE TPM SYSTEM"
message will no longer be displayed as long
as no system fault exists.General Information
The following regulatory statement applies to
all radio frequency (RF) devices equipped in
this vehicle:
This device complies with Part 15 of the FCC
Rules and with Industry Canada license-
exempt RSS standard(s). Operation is sub-
ject to the following two conditions:
(1) This device may not cause harmful inter-
ference, and
(2) This device must accept any interference
received, including interference that may
cause undesired operation.
NOTE:
Changes or modifications not expressly ap-
proved by the party responsible for compli-
ance could void the user’s authority to oper-
ate the equipment.
OCCUPANT RESTRAINT
SYSTEMS
Some of the most important safety features in
your vehicle are the restraint systems:
Occupant Restraint Systems Features
• Seat Belt Systems
• Supplemental Restraint Systems (SRS)Air Bags
• Supplemental Active Head Restraints
• Child Restraints
Some of the safety features described in this
section may be standard equipment on some
models, or may be optional equipment on
others. If you are not sure, ask your autho-
rized dealer.
Important Safety Precautions
Please pay close attention to the information
in this section. It tells you how to use your
restraint system properly, to keep you and
your passengers as safe as possible.
Here are some simple steps you can take to
minimize the risk of harm from a deploying
air bag:
1. Children 12 years old and under should always ride buckled up in a vehicle with a
rear seat.
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How To Engage The Automatic Locking Mode
1. Buckle the combination lap and shoulderbelt.
2. Grasp the shoulder portion and pull down- ward until the entire seat belt is extracted.
3. Allow the seat belt to retract. As the seat belt retracts, you will hear a clicking
sound. This indicates the seat belt is now
in the Automatic Locking Mode.
How To Disengage The Automatic Locking Mode
Unbuckle the combination lap/shoulder belt
and allow it to retract completely to disen-
gage the Automatic Locking Mode and acti-
vate the vehicle sensitive (emergency) lock-
ing mode.
WARNING!
• The seat belt assembly must be replaced if the switchable Automatic Locking Re-
tractor (ALR) feature or any other seat
belt function is not working properly
when checked according to the proce-
dures in the Service Manual.
WARNING!
• Failure to replace the seat belt assemblycould increase the risk of injury in colli-
sions.
• Do not use the Automatic Locking Mode
to restrain occupants who are wearing
the seat belt or children who are using
booster seats. The locked mode is only
used to install rear-facing or forward-
facing child restraints that have a har-
ness for restraining the child.
Supplemental Active Head Restraints (AHR)
These head restraints are passive, deployable
components, and vehicles with this equip-
ment cannot be readily identified by any
markings, only through visual inspection of
the head restraint. The head restraint will be
split in two halves, with the front half being
soft foam and trim, the back half being deco-
rative plastic.
How The Active Head Restraints (AHR) Work
The Occupant Restraint Controller (ORC) de-
termines whether the severity or type of rear
impact will require the Active Head Re- straints (AHR) to deploy. If a rear impact
requires deployment, both the driver and
front passenger seat AHRs will be deployed.
When AHRs deploy during a rear impact, the
front half of the head restraint extends for-
ward to minimize the gap between the back of
the occupant’s head and the AHR. This sys-
tem is designed to help prevent or reduce the
extent of injuries to the driver and front pas-
senger in certain types of rear impacts.
NOTE:
The Active Head Restraints (AHR) may or
may not deploy in the event of a front or side
impact. However, if during a front impact, a
secondary rear impact occurs, the AHR may
deploy based on the severity and type of the
impact.
119

Supplemental Restraint System (SRS)
Some of the safety features described in this
section may be standard equipment on some
models, or may be optional equipment on
others. If you are not sure, ask your autho-
rized dealer.
The air bag system must be ready to protect
you in a collision. The Occupant Restraint
Controller (ORC) monitors the internal cir-
cuits and interconnecting wiring associated
with the electrical Air Bag System Compo-
nents. Your vehicle may be equipped with the
following Air Bag System Components:
Air Bag System Components
• Occupant Restraint Controller (ORC)
• Air Bag Warning Light
• Steering Wheel and Column
• Instrument Panel
• Knee Impact Bolsters
• Driver and Front Passenger Air Bags
• Supplemental Side Air Bags
• Supplemental Knee Air Bags
• Front and Side Impact Sensors• Seat Belt Pretensioners
• Seat Belt Buckle Switch
Air Bag Warning Light
The ORC monitors the readiness of the
electronic parts of the air bag system when-
ever the ignition switch is in the START or
ON/RUN position. If the ignition switch is in
the OFF position or in the ACC position, the
air bag system is not on and the air bags will
not inflate.
The ORC contains a backup power supply
system that may deploy the air bag system
even if the battery loses power or it becomes
disconnected prior to deployment.
The ORC turns on the Air Bag Warning Light
in the instrument panel for approximately
four to eight seconds for a self-check when
the ignition switch is first in the ON/RUN
position. After the self-check, the Air Bag
Warning Light will turn off. If the ORC detects
a malfunction in any part of the system, it
turns on the Air Bag Warning Light, either
momentarily or continuously. A single chime
will sound to alert you if the light comes on
again after initial startup. The ORC also includes diagnostics that will
illuminate the instrument panel Air Bag
Warning Light if a malfunction is detected
that could affect the air bag system. The
diagnostics also record the nature of the
malfunction. While the air bag system is
designed to be maintenance free, if any of the
following occurs, have an authorized dealer
service the air bag system immediately.
• The Air Bag Warning Light does not come
on during the four to eight seconds when
the ignition switch is first in the ON/RUN
position.
• The Air Bag Warning Light remains on after the four to eight-second interval.
• The Air Bag Warning Light comes on inter- mittently or remains on while driving.
NOTE:
If the speedometer, tachometer, or any en-
gine related gauges are not working, the Oc-
cupant Restraint Controller (ORC) may also
be disabled. In this condition the air bags
may not be ready to inflate for your protec-
tion. Have an authorized dealer service the air
bag system immediately.
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