2018 JEEP WRANGLER UNLIMITED brake sensor

Towing With HSA
HSA will also provide assistance to mitigate
roll back while towing a trailer.
WARNING!
• If you use a trailer brake controller with
your trailer, the trailer brakes may be
activated and deactivated with the brake
switch. If so, there may not be enough
brake pressure to hold both the vehicle
and the trailer on a hill when the brake
pedal is released. In order to avoid roll-
ing down an incline while resuming ac-
celeration, manually activate the trailer
brake or apply more vehicle brake pres-
sure prior to releasing the brake pedal.
• HSA is not a parking brake. Always apply
the parking brake fully when exiting your
vehicle. Also, be certain to place the
transmission in PARK.
• Failure to follow these warnings can re-
sult in a collision or serious personal
injury.
Traction Control System (TCS)
This system monitors the amount of wheel
spin of each of the driven wheels. If wheel
spin is detected, the TCS may apply brake
pressure to the spinning wheel(s) and/or re-
duce engine power to provide enhanced ac-
celeration and stability. A feature of the TCS,
Brake Limited Differential (BLD), functions
similar to a limited slip differential and con-
trols the wheel spin across a driven axle. If
one wheel on a driven axle is spinning faster
than the other, the system will apply the
brake of the spinning wheel. This will allow
more engine torque to be applied to the wheel
that is not spinning. BLD may remain en-
abled even if TCS and ESC are in a reduced
mode.
Electronic Stability Control (ESC)
This system enhances directional control and
stability of the vehicle under various driving
conditions. ESC corrects for oversteering or
understeering of the vehicle by applying the
brake of the appropriate wheel(s) to assist in
counteracting the oversteer or understeer
condition. Engine power may also be reduced
to help the vehicle maintain the desired path.ESC uses sensors in the vehicle to determine
the vehicle path intended by the driver and
compares it to the actual path of the vehicle.
When the actual path does not match the
intended path, ESC applies the brake of the
appropriate wheel to assist in counteracting
the oversteer or understeer condition.
• Oversteer — when the vehicle is turning
more than appropriate for the steering
wheel position.
• Understeer — when the vehicle is turning
less than appropriate for the steering wheel
position.
The “ESC Activation/Malfunction Indicator
Light” located in the instrument cluster will
start to flash as soon as the ESC system
becomes active. The “ESC Activation/
Malfunction Indicator Light” also flashes
when the TCS is active. If the “ESC
Activation/Malfunction Indicator Light” be-
gins to flash during acceleration, ease up on
the accelerator and apply as little throttle as
possible. Be sure to adapt your speed and
driving to the prevailing road conditions.
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Trailer Sway Control (TSC)
TSC uses sensors in the vehicle to recognize
an excessively swaying trailer and will take
the appropriate actions to attempt to stop the
sway. TSC will become active automatically
once an excessively swaying trailer is recog-
nized.
NOTE:
TSC cannot stop all trailers from swaying.
Always use caution when towing a trailer and
follow the trailer tongue weight recommenda-
tions. Refer to “Trailer Towing” in “Starting
And Operating” for further information.
When TSC is functioning, the “ESC
Activation/Malfunction Indicator Light” will
flash, the engine power may be reduced and
you may feel the brakes being applied to
individual wheels to attempt to stop the
trailer from swaying. TSC is disabled when
the ESC system is in the “Partial Off” or “Full
Off” modes.WARNING!
If TSC activates while driving, slow the
vehicle down, stop at the nearest safe
location, and adjust the trailer load to
eliminate trailer sway.
Ready Alert Braking (RAB)
Ready Alert Braking may reduce the time
required to reach full braking during emer-
gency braking situations. It anticipates when
an emergency braking situation may occur by
monitoring how fast the throttle is released by
the driver. The EBC will prepare the brake
system for a panic stop.
Rain Brake Support (RBS)
Rain Brake Support may improve braking
performance in wet conditions. It will periodi-
cally apply a small amount of brake pressure
to remove any water buildup on the front
brake rotors. It functions when the wind-
shield wipers are in LO or HI speed. When
Rain Brake Support is active, there is no
notification to the driver and no driver inter-
action is required.
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 ve-
hicle 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 vehicle 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.
89

Feedback To The Driver
The instrument cluster has an HDC icon and
the HDC switch has an indicator light, which
offers feedback to the driver about the state
HDC is in.
• The cluster icon and switch indicator light
will illuminate and remain on solid when
HDC is enabled or activated. This is the
normal operating condition for HDC.
• The cluster icon and switch indicator light
will flash for several seconds then extin-
guish when the driver pushes the HDC
switch but enable conditions are not met.
• The cluster icon and switch indicator light
will flash for several seconds then extin-
guish when HDC disables due to excess
speed.
• The cluster icon and switch indicator light
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 descend-
ing hills. The driver must remain attentive
to the driving conditions and is responsible
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 highway 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 out-
side rear view mirrors to let the driver know
that the system is operational. The 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 approxi-
mately 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
Rear Detection Zones
91

STARTING AND OPERATING
STARTING THE ENGINE.......142
Normal Starting — Gasoline Engine . . .142
Normal Starting — Diesel Engine. . . .145
ENGINE BREAK-IN RECOMMENDA-
TIONS....................146
AUTOMATIC TRANSMISSION . . .147
Ignition Park Interlock...........148
Brake/Transmission Shift Interlock
System....................148
Eight–Speed Automatic Transmission . .148
FOUR–WHEEL DRIVE OPERA-
TION.....................150
Four-Position Transfer Case........150
Five-Position Transfer Case........153
Trac-Lok Rear Axle — If Equipped . . .155
Axle Lock (Tru-Lok) — Rubicon Models
.........................156
Electronic Sway Bar Disconnect — If
Equipped...................156
STOP/START SYSTEM — AUTOMATIC
TRANSMISSION (IF EQUIPPED)
. .157
Automatic Mode...............158
Possible Reasons The Engine Does Not
Autostop...................158
To Start The Engine While In Autostop
Mode.....................159
To Manually Turn Off The Stop/Start
System....................159
To Manually Turn On The Stop/Start
System....................160
System Malfunction............160
SPEED CONTROL...........160
To Activate..................161
To Set A Desired Speed..........161
To Vary The Speed Setting.........161
To Accelerate For Passing.........162
To Resume Speed.............162
To Deactivate................162
PARKSENSE REAR PARK ASSIST —
IF EQUIPPED...............163
ParkSense Sensors.............163
Enabling And Disabling ParkSense . . .163
ParkSense System Usage Precautions . .163
PARKVIEW REAR BACK UP CAM-
ERA — IF EQUIPPED..........165
REFUELING THE VEHICLE.....166
Fuel Filler Cap...............166
Loose Fuel Filler Cap Message......167
REFUELING THE VEHICLE — DIE-
SEL......................167
Adblue (UREA) — If Equipped......168
TRAILER TOWING...........171
Trailer Towing Weights (Maximum Trailer
Weight Ratings)...............171
RECREATIONAL TOWING (BEHIND
MOTORHOME, ETC.).........171
Towing This Vehicle Behind Another
Vehicle....................171
Recreational Towing — Four-Wheel Drive
Models....................172
STARTING AND OPERATING
141

• Drivers door is ajar or in conditions where
driver door is removed an additional trigger
would be if the driver is off the seat (seat
pad sensor detects driver missing).
• Vehicle is not in PARK
• Vehicle Speed is 0 mph (0 km/h)
• Ignition switched from RUN to OFF
NOTE:
For Keyless Go equipped vehicles, The en-
gine will turn off and the ignition switch will
change to ACC mode. After 30 minutes the
ignition switches to OFF automatically, un-
less the driver turns the ignition switch OFF.
If the vehicle is not in PARK and the driver exits
the vehicle with the engine running, the vehicle
may AutoPark.
AutoPark will engage when all of these con-
ditions are met:
• Vehicle is equipped with an 8-speed trans-
mission
• Drivers door is ajar or in conditions where
driver door is removed an aditional trigger
would be if the driver is off the seat (seat
pad sensor detects driver missing).• Vehicle is not in PARK
• Driver’s door is removed
• Vehicle speed is 1.2 mph (2.0 km/h) or less
• Driver’s seat belt is unbuckled
• Driver’s door is ajar
• Brake Pedal is not depressed
The MESSAGE “AutoPark Engaged Shift to P
then Shift to Gear” will display in the instru-
ment cluster.
NOTE:
In some cases the ParkSense graphic will be
displayed in the instrument cluster. In these
cases, the shifter must be returned to “P” to
select desired gear.
If the driver shifts into PARK while moving, the
vehicle may AutoPark.
AutoPark will engageONLYwhen vehicle
speed is 1.2 mph (2.0 km/h) or less.
The MESSAGE “Vehicle Speed is Too High to
Shift to P” will be displayed in the instrument
cluster if vehicle speed is above 1.2 mph
(2.0 km/h).WARNING!
If vehicle speed is above 1.2 mph
(2.0 km/h), the transmission will default
to NEUTRAL until the vehicle speed drops
below 1.2 mph (1.9 km/h). A vehicle left
in the NEUTRAL position can roll. As an
added precaution, always apply the park-
ing brake when exiting the vehicle.
4WD LOW
AutoPark will be disabled when operating the
vehicle in 4WD LOW.
The MESSAGE “AutoPark Disabled” will be
displayed in the instrument cluster.
Additional customer warnings will be given
when both of these conditions are met:
• Vehicle is not in PARK
• Driver’s Door is ajar
The MESSAGE “AutoPark Not Engaged” will
be displayed in the instrument cluster. A
warning chime will continue until you shift
the vehicle into PARK or the Driver’s Door is
closed.
STARTING AND OPERATING
144

Cavity Cartridge Fuse Micro Fuse Description
F76 – 20 Amp Yellow ECM (GAS)/PCM (DSL)
(*)
F77 – 10 Amp Red HTD MIRRORS
F78 – 10 Amp Red COMP/INTRUSION/SIREN/INTRUSION SENSORS
F79 – 20 Amp Yellow SMART BAR CTRL MOD
(*)
F80 – 15 Amp Blue Powertrain Control Module (PCM)
(*)
F81 30 Amp Pink – REAR DEFROSTER (EBL)
F82 30 Amp Pink – FUEL HTR — If Equipped
(*)
F83 60 Amp Yellow GLOW PLUG — If Equipped
(*)
F84 30 Amp Pink – UREA HTR CTRL UNIT — If Equipped
(*)
F85 – 10 Amp Red PM SENSOR — If Equipped
(*)
F86 30 Amp Pink – BRAKE VAC PMP2—IfEquipped
(*)
F87 – 10 Amp Red SUPPLY/PURGING PMP — If Equipped
(*)
F88 20 Amp Blue – NOx SENSOR #1/ #2 — IF Equipped
(*)
F89 – 10 Amp Red Steering Column Control Module (SCCM)/ Cruise Control
(CRUISE CTL)/Digital TV (DTV)
(*)
187