2013 JEEP GRAND CHEROKEE sensor

Display Warnings And Maintenance
“Clean Radar Sensor In Front Of Vehicle” Warning
The ACC “Clean Radar Sensor In Front Of Vehicle”
warning will display when conditions temporarily limit
system performance. This most often occurs at times of
poor visibility, such as in snow or heavy rain. The ACC
system may also become temporarily blinded due to
obstructions, such as mud, dirt or ice. In these cases, the
EVIC will display “Clean Radar Sensor In Front Of
Vehicle” and the system will deactivate.
The “Clean Radar Sensor In Front Of Vehicle” message
can sometimes be displayed while driving in highly
reflective areas (i.e. tunnels with reflective tiles, or ice and
snow). The ACC system will recover after the vehicle has
left these areas. Under rare conditions, when the radar is
not tracking any vehicles or objects in its path this
warning may temporarily occur.NOTE:
If the ACC “Clean Radar Sensor In Front Of
Vehicle” warning is active Normal (Fixed Speed) Cruise
Control is still available. For additional information refer
to “Normal (Fixed Speed) Cruise Control Mode” in this
section.
Clean Radar Sensor Warning
240 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

If weather conditions are not a factor, the driver should
examine the sensor. It may require cleaning or removal of
an obstruction. The sensor is located in the center of the
vehicle behind the lower grille.
To keep the ACC System operating properly, it is impor-
tant to note the following maintenance items:
•Always keep the sensor clean. Carefully wipe the
sensor lens with a soft cloth. Be cautious not to damage
the sensor lens.
• Do not remove any screws from the sensor. Doing so
could cause an ACC system malfunction or failure and
require a sensor realignment.
• If the sensor is damaged due to a collision, see your
authorized dealer for service.
• Do not attach or install any accessories near the sensor,
including transparent material or aftermarket grilles.
Doing so could cause an ACC system failure or
malfunction. When the condition that deactivated the system is no
longer present, the system will return to the “Adaptive
Cruise Control Off” state and will resume function by
simply reactivating it.
NOTE:
•
If the “Clean Radar Sensor In Front Of Vehicle”
message occurs frequently (e.g. more than once on
every trip) without any snow, rain, mud, or other
obstruction, have the radar sensor realigned at your
authorized dealer.
• Installing a snow plow, front-end protector, an after-
market grille or modifying the grille is not recom-
mended. Doing so may block the sensor and inhibit
ACC operation.
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UNDERSTANDING THE FEATURES OF YOUR VEHICLE 241

Removing ACC Sensor For Off-Roading
NOTE:When off-roading, it may be advisable to remove
the ACC sensor. The sensor is located behind the front
lower grille in the center of the vehicle. After removing
the lower fascia, you may remove the lower sensor and
bracket assembly.
To remove the sensor follow these instructions:
1. Unplug the connector by depressing the two tabs on the connector and pulling it out. Do not pull by the
wiring or use any tools to remove the connector.
2. Remove the wiring christmas tree attachment from the back of the bracket.
3. Remove the two M6 fasteners that connect the bracket to the bumper. NOTE:
Do not change the adjustment fasteners or pull
the sensor off of the bracket. Doing so may misalign the
sensor.
Store the sensor and bracket assembly in a safe location.
The wiring and connector must be stowed properly after
the sensor and bracket assembly is removed.
A connector plug is stowed on top of the bumper beam.
Insert the wiring connector into the connector plug.
NOTE: When the sensor is removed, Adaptive Cruise
Control, Normal Cruise Control, and Forward Collision
Warning will not be available. The cluster will display
the warning “ACC/FCW Unavailable - Service Radar
Sensor.”
242 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

To reinstall the sensor and bracket assembly reverse the
process above. The fastener torque required to assembly
the bracket back to the beam is 6.6 ft lbs (9 N·m).
ACC Unavailable Warning
If the system turns off, and the EVIC displays “ACC/
FCW Unavailable, Vehicle System Error”, there may be a
temporary malfunction that limits ACC functionality.
Although the vehicle is still drivable under normal
conditions, ACC will be temporarily unavailable. If this
occurs, try activating ACC again later, following a key
cycle. If the problem persists, see your authorized dealer.
Service ACC Warning
If the system turns off, and the EVIC displays “ACC/
FCW Unavailable Service Radar Sensor”, it indicates
there is an internal system fault. Although the vehicle is
still drivable under normal conditions, have the system
checked by an authorized dealer.
Precautions While Driving With ACC
In certain driving situations, ACC may have detection
issues. In these cases, ACC may brake late or unexpect-
edly. The driver needs to stay alert and may need to
intervene.
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UNDERSTANDING THE FEATURES OF YOUR VEHICLE 243

Forward Collision Warning — If Equipped
The Forward Collision Warning (FCW) system provides
the driver with audible and visual warnings (within the
EVIC) when it detects a potential frontal collision. The
warnings are intended to provide the driver with enough
time to react and avoid the potential collision.
FCW monitors the information from the forward looking
sensor as well as the Electronic Brake Controller (EBC),
wheel speed sensors, i.e., to calculate a probable rear-end
collision. When the system determines that a rear-end
collision is probable a warning message (both audible
and visual) will be displayed on the EVIC. When the
system determines a collision with the vehicle in front of
you is no longer probable, the warning message will be
deactivated.
FCW Message
250 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

NOTE:
•The system will retain the last setting selected by the
driver after ignition shut down.
• FCW will not react to irrelevant objects such as over-
head objects, ground reflections, objects not in the path
of the car, stationary objects that are far away, oncom-
ing traffic, or leading vehicles with the same or higher
rate of speed.
• FCW will be disabled like ACC below with the un-
available screens.
FCW Unavailable Warning
If the system turns off, and the EVIC displays “ACC/
FCW Unavailable, Vehicle System Error”, there may be a
temporary malfunction that limits FCW functionality.
Although the vehicle is still drivable under normal
conditions, FCW will be temporarily unavailable. If this occurs, try activating FCW again later, following a key
cycle. If the problem persists, see your authorized dealer.
Service FCW Warning
If the system turns off, and the EVIC displays “ACC/
FCW Unavailable Service Radar Sensor”, it indicates
there is an internal system fault. Although the vehicle is
still drivable under normal conditions, have the system
checked by an authorized dealer.
PARKSENSE
REAR PARK ASSIST — IF
EQUIPPED
The ParkSense Rear Park Assist system provides visual
and audible indications of the distance between the rear
fascia and a detected obstacle when backing up, e.g.
during a parking maneuver. Refer to ParkSense System
Usage Precautions for limitations of this system and
recommendations.
254 UNDERSTANDING THE FEATURES OF YOUR VEHICLE

ParkSensewill retain the last system state (enabled or
disabled) from the last ignition cycle when the ignition is
changed to the ON/RUN position.
ParkSense can be active only when the shift lever is in
REVERSE. If ParkSense is enabled at this shift lever
position, the system will remain active until the vehicle
speed is increased to approximately 11 mph (18 km/h) or
above. The system will become active again if the vehicle
speed is decreased to speeds less than approximately
10 mph (16 km/h).ParkSense Sensors
The four ParkSense sensors, located in the rear fascia/
bumper, monitor the area behind the vehicle that is
within the sensors’ field of view. The sensors can detect
obstacles from approximately 12 in (30 cm) up to 79 in
(200 cm) from the rear fascia/bumper in the horizontal
direction, depending on the location, type and orienta-
tion of the obstacle.
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UNDERSTANDING THE FEATURES OF YOUR VEHICLE 255

“Electronic Vehicle Information Center (EVIC)” in “Un-
derstanding Your Instrument Panel” for further informa-
tion. When the shift lever is moved to REVERSE and the
system is disabled, the EVIC will display the “PARK
ASSIST SYSTEM OFF” message for as long as the vehicle
is in REVERSE.
The ParkSenseswitch LED will be ON when
ParkSense is disabled or defective. The ParkSense 
switch LED will be OFF when the system is enabled.
Service The ParkSense Rear Park Assist System
When the ParkSenseRear Park Assist System is mal-
functioning, the instrument cluster will actuate a single
chime, once per ignition cycle, and it will display the
“CLEAN PARK ASSIST SENSORS” or the “SERVICE
PARK ASSIST SYSTEM” message. Refer to “Electronic
Vehicle Information Center (EVIC)” in “Understanding
Your Instrument Panel” for further information. When
the shift lever is moved to REVERSE and the system has detected a faulted condition, the EVIC will display the
“PARK ASSIST SYSTEM OFF” message for as long as the
vehicle is in REVERSE. Under this condition, ParkSense
will not operate.
If “CLEAN PARK ASSIST SENSORS” appears in the
Electronic Vehicle Information Center (EVIC) make sure
the outer surface and the underside of the rear fascia/
bumper is clean and clear of snow, ice, mud, dirt or other
obstruction and then cycle the ignition. If the message
continues to appear, see an authorized dealer.
If “SERVICE PARK ASSIST SYSTEM” appears in the
EVIC, see an authorized dealer.
Cleaning The ParkSense
System
Clean the ParkSense sensors with water, car wash soap
and a soft cloth. Do not use rough or hard cloths. Do not
scratch or poke the sensors. Otherwise, you could dam-
age the sensors.
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UNDERSTANDING THE FEATURES OF YOUR VEHICLE 261