Chrysler 300 2011 Owner's Manual page 201

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.
UNDERSTANDING THE FEATURES OF YOUR VEHICLE 199
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: Installing a vehicle front-end protector or an
aftermarket grille or modifying the grille is not recom-
mended. Doing so may block the sensor and inhibit ACC
operation.
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.
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