Jeep Wrangler (2018 year). Manual — part 14

Hill Descent Control (HDC) — If Equipped

HDC is intended for low speed off road driving while in

4WD Low Range. HDC maintains vehicle speed while

descending hills during various driving situations. HDC

controls vehicle speed by actively controlling the brakes.

HDC has three states:

1. Off (feature is not enabled and will not activate).
2. Enabled (feature is enabled and ready but activation

conditions are not met, or driver is actively overriding

with brake or throttle application).

3. Active (feature is enabled and actively controlling ve-

hicle speed).

Enabling HDC

HDC is enabled by pushing the HDC switch, but the

following conditions must also be met to enable HDC:
• Driveline is in 4WD Low Range
• Vehicle speed is below 5 mph (8 km/h).
• Parking brake is released.
• Driver door is closed. (If doors are attached, then door

must be closed. if doors are detached, then driver

seatbelt must be buckled.)

Activating HDC

Once HDC is enabled it will activate automatically if

driven down a grade of sufficient magnitude. The set speed

for HDC is selectable by the driver, and can be adjusted by

using the gear shift +/-. The following summarizes the

HDC set speeds:

HDC Target Set Speeds
• P = No set speed. HDC may be enabled but will not

activate

• R = 0.6 mph (1 km/h)
• N = 1.2 mph (2 km/h)
• D = 0.6 mph (1 km/h)
• 1st = 0.6 mph (1 km/h)
• 2nd = 1.2 mph (2 km/h)
• 3rd = 1.8 mph (3 km/h)
• 4th = 2.5 mph (4 km/h)
• 5th = 3.1 mph (5 km/h)
• 6th = 3.7 mph (6 km/h)
• 7th = 4.3 mph (7 km/h)
• 8th = 5.0 mph (8 km/h)

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• 9th = 5.6 mph (9 km/h) – If Equipped

NOTE:

During HDC the +/- shifter input is used for HDC

target speed selection, but will not affect the gear chosen by

the transmission. When actively controlling HDC the trans-

mission will shift appropriately for the driver-selected set

speed and corresponding driving conditions.

Driver Override

The driver may override HDC activation with throttle or

brake application at anytime.

Deactivating HDC

HDC will be deactivated but remain available if any of the

following conditions occur:
• Driver overrides HDC set speed with throttle or brake

application.

• Vehicle speed exceeds 20 mph (32 km/h) but remains

below 40 mph (64 km/h).

• Vehicle is on a downhill grade of insufficient magnitude,

is on level ground, or is on an uphill grade.

• Vehicle is shifted to park.

Disabling HDC

HDC will be deactivated and disabled if any of the

following conditions occur:
• The driver pushes the HDC switch.
• The driveline is shifted out of 4WD Low Range.
• The parking brake is applied.
• Driver door opens (Driver door opens if doors are

attached or driver seatbelt is unbuckled if doors are

detached).

• The vehicle is driven greater than 20 mph (32 km/h) for

greater than 70 seconds.

• The vehicle is driven greater than 40 mph (64 km/h)

(HDC exits immediately).

• HDC detects excessive brake temperature.

Feedback To The Driver

The instrument cluster has an HDC icon and the HDC

switch has an LED icon, which offers feedback to the driver

about the state HDC is in.
• The cluster icon and switch lamp will illuminate and

remain on solid when HDC is enabled or activated. This

is the normal operating condition for HDC.

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• The cluster icon and switch lamp will flash for several

seconds then extinguish when the driver pushes the

HDC switch but enable conditions are not met.

• The cluster icon and switch lamp will flash for several

seconds then extinguish when HDC disables due to

excess speed.

• The cluster icon and switch lamp will flash when HDC

deactivates due to overheated brakes. The flashing will

stop and HDC will activate again once the brakes have

cooled sufficiently.

WARNING!

HDC is only intended to assist the driver in controlling
vehicle speed when descending hills. The driver must
remain attentive to the driving conditions and is re-
sponsible for maintaining a safe vehicle speed.

AUXILIARY DRIVING SYSTEMS

Blind Spot Monitoring (BSM) — If Equipped

The Blind Spot Monitoring (BSM) system uses two radar-

based sensors, located inside the taillights, to detect high-

way licensable vehicles (automobiles, trucks, motorcycles,

etc.) that enter the blind spot zones from the rear/front/

side of the vehicle.

When the vehicle is started, the BSM warning light will

momentarily illuminate in both outside rear view mirrors

to let the driver know that the system is operational. The

Rear Detection Zones

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BSM system sensors operate when the vehicle is in any

forward gear or REVERSE and enters stand-by mode when

the vehicle is in PARK.
The BSM detection zone covers approximately one lane

width on both sides of the vehicle 12 ft (3.8 m). The zone

length starts at the outside rear view mirror and extends

approximately 10 ft (3 m) beyond the rear bumper of the

vehicle. The BSM system monitors the detection zones on

both sides of the vehicle when the vehicle speed reaches

approximately 6 mph (10 km/h) or higher and will alert

the driver of vehicles in these areas.

NOTE:
• The BSM system DOES NOT alert the driver about

rapidly approaching vehicles that are outside the detec-

tion zones.

• The BSM system detection zone DOES NOT change if

your vehicle is towing a trailer. Therefore, visually verify

the adjacent lane is clear for both your vehicle and trailer

before making a lane change. If the trailer or other object

(i.e., bicycle, sports equipment) extends beyond the side

of your vehicle, this may result in the BSM warning light

remaining illuminated the entire time the vehicle is in a

forward gear.

• The Blind Spot Monitoring (BSM) system may experi-

ence drop outs (blinking on and off) of the side mirror

Warning Indicator lamps when a motorcycle or any

small object remains at the side of the vehicle for

extended periods of time (more than a couple of sec-

onds).

The area on taillights, where the radar sensors are located,

must remain free of snow, ice, and dirt/road contamination

so that the BSM system can function properly. Do not block

the taillights where the radar sensors are located with

foreign objects (bumper stickers, bicycle racks, etc.).

BSM Radar Location (Driver Side Shown)

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The BSM system notifies the driver of objects in the

detection zones by illuminating the BSM warning light

located in the outside mirrors in addition to sounding an

audible (chime) alert and reducing the radio volume. Refer

to “Modes Of Operation” for further information.

The BSM system monitors the detection zone from three

different entry points (side, rear, front) while driving to see

if an alert is necessary. The BSM system will issue an alert

during these types of zone entries.

Entering From The Side

Vehicles that move into your adjacent lanes from either

side of the vehicle.

Warning Light Location

Side Monitoring

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Entering From The Rear

Vehicles that come up from behind your vehicle on either

side and enter the rear detection zone with a relative speed

of less than 30 mph (48 km/h).

Overtaking Traffic

If you pass another vehicle slowly with a relative speed less

than 15 mph (24 km/h) and the vehicle remains in the

blind spot for approximately 1.5 seconds, the warning light

will be illuminated. If the difference in speed between the

two vehicles is greater than 15 mph (24 km/h), the warning

light will not illuminate.

Rear Monitoring

Overtaking/Approaching

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The BSM system is designed not to issue an alert on

stationary objects such as guardrails, posts, walls, foliage,

berms, etc. However, occasionally the system may alert on

such objects. This is normal operation and your vehicle

does not require service.

The BSM system will not alert you of objects that are

traveling in the opposite direction of the vehicle in adjacent

lanes.

Overtaking/Passing

Stationary Objects

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WARNING!

The Blind Spot Monitoring system is only an aid to
help detect objects in the blind spot zones. The BSM
system is not designed to detect pedestrians, bicyclists,
or animals. Even if your vehicle is equipped with the
BSM system, always check your vehicle’s mirrors,
glance over your shoulder, and use your turn signal
before changing lanes. Failure to do so can result in
serious injury or death.

Rear Cross Path (RCP)

The Rear Cross Path (RCP) feature is intended to aid the

driver when backing out of parking spaces where their

vision of oncoming vehicles may be blocked. Proceed

slowly and cautiously out of the parking space until the

rear end of the vehicle is exposed. The RCP system will

then have a clear view of the cross traffic and if an

oncoming vehicle is detected, alert the driver.

RCP monitors the rear detection zones on both sides of the

vehicle, for objects that are moving toward the side of the

vehicle with a minimum speed of approximately 3 mph

Opposing Traffic

RCP Detection Zones

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(5 km/h), to objects moving a maximum of approximately

20 mph (32 km/h), such as in parking lot situations.

NOTE:

In a parking lot situation, oncoming vehicles can be

obscured by vehicles parked on either side. If the sensors

are blocked by other structures or vehicles, the system will

not be able to alert the driver.
When RCP is on and the vehicle is in REVERSE, the driver

is alerted using both the visual and audible alarms, includ-

ing reducing the radio volume.

WARNING!

Rear Cross Path Detection (RCP) is not a back up aid
system. It is intended to be used to help a driver detect
an oncoming vehicle in a parking lot situation. Drivers
must be careful when backing up, even when using
RCP. Always check carefully behind your vehicle, look
behind you, and be sure to check for pedestrians,
animals, other vehicles, obstructions, and blind spots
before backing up. Failure to do so can result in serious
injury or death.

Modes Of Operation

Three selectable modes of operation are available in the

Uconnect System. Refer to “Uconnect Settings” in “Multi-

media” for further information.

Blind Spot Alert Lights Only

When operating in Blind Spot Alert mode, the BSM system

will provide a visual alert in the appropriate side view

mirror based on a detected object. However, when the

system is operating in Rear Cross Path (RCP) mode, the

system will respond with both visual and audible alerts

when a detected object is present. Whenever an audible

alert is requested, the radio is muted.

Blind Spot Alert Lights/Chime

When operating in Blind Spot Alert Lights/Chime mode,

the BSM system will provide a visual alert in the appro-

priate side view mirror based on a detected object. If the

turn signal is then activated, and it corresponds to an alert

present on that side of the vehicle, an audible chime will

also be sounded. Whenever a turn signal and detected

object are present on the same side at the same time, both

the visual and audible alerts will be issued. In addition to

the audible alert the radio (if on) will also be muted.

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NOTE:

Whenever an audible alert is requested by the BSM

system, the radio is also muted.
When the system is in RCP, the system shall respond with

both visual and audible alerts when a detected object is

present. Whenever an audible alert is requested, the radio

is also muted. Turn/hazard signal status is ignored; the

RCP state always requests the chime.

Blind Spot Alert Off

When the BSM system is turned off there will be no visual

or audible alerts from either the BSM or RCP systems.

NOTE:

The BSM system will store the current operating

mode when the vehicle is shut off. Each time the vehicle is

started the previously stored mode will be recalled and

used.

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 subject to the following two conditions:
1. This device may not cause harmful interference.

2. This device must accept any interference received, in-

cluding interference that may cause undesired opera-

tion.

NOTE:

Changes or modifications not expressly approved

by the party responsible for compliance could void the

user’s authority to operate the equipment.

Tire Pressure Monitor System (TPMS)

The Tire Pressure Monitor System (TPMS) will warn the

driver of a low tire pressure based on the vehicle recom-

mended cold placard pressure.
The tire pressure will vary with temperature by approxi-

mately 1 psi (7 kPa) for every 12°F (6.5°C). This means that

when the outside temperature decreases, the tire pressure

will decrease. Tire pressure should always be set based on

cold inflation tire pressure. This is defined as the tire

pressure after the vehicle has not been driven for at least

three hours, or driven less than 1 mile (1.6 km) after a three

hour period. The cold tire inflation pressure must not

exceed the maximum inflation pressure molded into the

tire sidewall. Refer to “Tires” in “Servicing And Mainte-

nance” for information on how to properly inflate the

vehicle’s tires. The tire pressure will also increase as the

vehicle is driven. This is normal and there should be no

adjustment for this increased pressure.

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The TPMS will warn the driver of a low tire pressure if the

tire pressure falls below the low-pressure warning limit for

any reason, including low temperature effects and natural

pressure loss through the tire.
The TPMS will continue to warn the driver of low tire

pressure as long as the condition exists, and will not turn

off until the tire pressure is at or above the recommended

cold placard pressure. Once the low tire pressure warning

(Tire Pressure Monitoring Telltale Light) illuminates, you

must increase the tire pressure to the recommended cold

placard pressure in order for the Tire Pressure Monitoring

Telltale Light to turn off.

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 placard pressure in order to turn the

Tire Pressure Monitoring Telltale Light off.
The system will automatically update and the Tire Pressure

Monitoring Telltale Light will turn off once the system

receives the updated tire pressures. 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.
For example, your vehicle may have a recommended cold

(parked for more than three hours) placard pressure of 33

psi (227 kPa). If the ambient temperature is 68°F (20°C) and

the measured tire pressure is 28 psi (193 kPa), a tempera-

ture drop to 20°F (-7°C) will decrease the tire pressure to

approximately 24 psi (165 kPa). This tire pressure is low

enough to turn on the Tire Pressure Monitoring Telltale

Light. Driving the vehicle may cause the tire pressure to

rise to approximately 28 psi (193 kPa), but the Tire Pressure

Monitoring Telltale Light will still be on. In this situation,

the Tire Pressure Monitoring Telltale Light will turn off

only after the tires are inflated to the vehicle’s recom-

mended cold placard pressure value.

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 placard pressure in order to turn the

Tire Pressure Monitoring Telltale Light off.

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 op-
eration or sensor damage may result when using
replacement equipment that is not of the same size,
type, and/or style. The TPM sensor is not designed

(Continued)

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CAUTION! (Continued)

for use on aftermarket wheels, and may contribute to
a poor overall system performance. Customers are
encouraged to use OEM wheels to assure TPMS
feature operation.

• Using aftermarket tire sealants may cause the Tire

Pressure Monitoring System (TPMS) sensor to be-
come inoperable. After using an aftermarket tire
sealant it is recommended that you take your vehicle
to an authorized dealer to have your sensor function
checked.

• After inspecting or adjusting the tire pressure always

reinstall the valve stem cap. This will prevent mois-
ture and dirt from entering the valve stem, which
could damage the TPMS sensor.

NOTE:
• The TPMS is not intended to replace normal tire care and

maintenance, or to provide warning of a tire failure or

condition.

• The TPMS should not be used as a tire pressure gauge

while adjusting your tire pressure.

• Driving on a significantly underinflated tire causes the

tire to overheat and can lead to tire failure. Underinfla-

tion also reduces fuel efficiency and tire tread life, and

may affect the vehicle’s handling and stopping ability.

• The TPMS is not a substitute for proper tire mainte-

nance, and it is the driver’s responsibility to maintain

correct tire pressure using an accurate tire pressure

gauge, even if underinflation has not reached the level to

trigger illumination of the Tire Pressure Monitoring

Telltale Light.

• Seasonal temperature changes will affect tire pressure,

and the TPMS will monitor the actual tire pressure in the

tire.

System Operation

The Tire Pressure Monitor System (TPMS) uses wireless

technology with wheel rim mounted electronic sensors to

monitor tire pressure levels. Sensors, mounted to each

wheel as part of the valve stem, transmit tire pressure

readings to the receiver module.

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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 TPMS consists of the following components:
• Receiver module
• Four tire pressure monitoring sensors
• Various tire pressure monitoring system messages,

which display in the instrument cluster

• Tire pressure monitoring telltale light

Tire Pressure Monitoring Low Pressure Warnings

The Tire Pressure Monitoring Telltale Light will

illuminate in the instrument cluster and a chime

will sound when tire pressure is low in one or more of the

four active road tires. In addition, the instrument cluster

will display a

⬙Tire Low⬙ message for a minimum of five

seconds, an

⬙Inflate to XX⬙ message and a graphic showing

the pressure values of each tire with the low tire pressure

values in a different color.

Should this occur, you should stop as soon as possible and

inflate the tires with low pressure (those in a different color

Tire Pressure Monitoring Display

Tire Pressure Monitoring Low Pressure Warning

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in the instrument cluster graphic) to the vehicle’s recom-

mended cold placard pressure value as shown in the

⬙Inflate to XX⬙ message. Once the system receives the

updated tire pressures, the system will automatically up-

date, the pressure values in the graphic display in the

instrument cluster will return to their original color, and

the Tire Pressure Monitoring Telltale Light will turn off.

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 placard pressure in order to turn the

Tire Pressure Monitoring Telltale Light off.

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.

Service TPMS Warning

When a system fault is detected, the Tire Pressure Moni-

toring Telltale Light will flash on and off for 75 seconds and

then remain on solid. The system fault will also sound a

chime. In addition, the instrument cluster will display a

⬙SERVICE TIRE PRESSURE SYSTEM⬙ message for a mini-

mum of five seconds and then display dashes (- -) in place

of the pressure value to indicate which sensor is not being

received.

If the ignition key 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, and the “SERVICE TIRE PRESSURE

SYSTEM” message will no longer display, and a pressure

value will display in place of the dashes. A system fault can

occur due to any of the following:
• Jamming due to electronic devices or driving next to

facilities emitting the same radio frequencies as the

TPMS sensors.

• Installing some form of aftermarket window tinting that

affects radio wave signals.

• Lots of snow or ice around the wheels or wheel hous-

ings.

• Using tire chains on the vehicle.
• Using wheels/tires not equipped with TPMS sensors.

Vehicles With Compact Spare or Non-Matching Full Size
Spare

1. The compact spare tire or non-matching full size does

not have a tire pressure monitoring sensor. Therefore,

the TPMS will not monitor the pressure in the compact

spare tire.

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2. If you install the compact or non-matching full size

spare tire in place of a road tire that has a pressure below

the low-pressure warning limit, upon the next ignition

key cycle, the TPMS Telltale Light will remain on and a

chime will sound. In addition, the graphic in the instru-

ment cluster will still display a different color pressure

value and an

⬙Inflate to XX⬙ message.

3. After driving the vehicle for up to 20 minutes above

15 mph (24 km/h), the TPMS Telltale Light will flash on

and off for 75 seconds and then remain on solid. In

addition, the instrument cluster will display a “Service

Tire Pressure System” message for five seconds and then

display dashes (- -) in place of the pressure value.

4. For each subsequent ignition key cycle, a chime will

sound, the TPMS Telltale Light will flash on and off for

75 seconds and then remain on solid, and the instrument

cluster will display a “SERVICE TIRE PRESSURE SYS-

TEM” message for five seconds and then display dashes

(- -) in place of the pressure value.

5. Once you repair or replace the original road tire and

reinstall it on the vehicle in place of the compact spare or

non-matching full size, the TPMS will update automati-

cally. In addition, the TPMS Telltale Light will turn off

and the graphic in the instrument cluster 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.

Vehicles With a Full Size Matching Spare

1. If your vehicle is equipped with a matching full-size

spare wheel and tire assembly, it has a tire pressure

monitoring sensor, and can be monitored by the Tire

Pressure Monitoring System (TPMS) when swapped

with a low pressure road tire.

2. In the event that the matching full-size spare tire is

swapped with a low pressure road tire, the next ignition

switch cycle will still show the Tire Pressure Monitoring

Telltale Light to be on, a chime to sound, an Inflate to XX

message to appear in the instrument cluster, and the

graphic display will still show the low tire pressure

value in a different color.

3. Driving the vehicle for up to 20 minutes above 15 mph

(24 km/h) will turn off the Tire Pressure Monitoring

Telltale Light as long as none of road tires are below the

low pressure warning threshold.

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TPMS Deactivation — If Equipped

The TPMS can be deactivated if replacing all four wheel

and tire assemblies (road tires) with wheel and tire assem-

blies 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 Monitoring (TPM) Sensors. Then, drive the ve-

hicle for 20 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

display the “SERVICE TIRE PRESSURE 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 TIRE PRESSURE

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 TPMS

sensors. Then, drive the vehicle for up to 20 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 TIRE

PRESSURE SYSTEM” message and then display pressure

values in place of the dashes. On the next ignition cycle the

⬙SERVICE TIRE PRESSURE 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 subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) This device must accept any interference received,

including interference that may cause undesired operation.

NOTE:

Changes or modifications not expressly approved

by the party responsible for compliance could void the

user’s authority to operate the equipment.

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