2008 Mercury Grand Marquis sensor

Window lock
The window lock feature allows only
the driver to operate the power
windows.
To lock out all the window controls
except for the driver’s press the left
side of the control. Press the right
side to restore the window controls.
INTERIOR MIRROR
The interior rear view mirror has two pivot points on the support arm
which lets you adjust the mirror UP or DOWN and from SIDE to SIDE.
Do not adjust the mirror while the vehicle is in motion.
Automatic dimming interior rear view mirror (if equipped)
Your vehicle may be equipped with
an interior rear view mirror which
has an auto-dimming function. The
electronic day/night mirror will
change from the normal (high
reflective) state to the non-glare
(darkened) state when bright lights
(glare) reach the mirror. When the
mirror detects bright light from behind the vehicle, it will automatically
adjust (darken) to minimize glare.
The mirror will automatically return to the normal state whenever the
vehicle is placed in R (Reverse) to ensure a bright clear view when
backing up.
Do not block the sensors on the front and back of the interior
rear view mirror since this may impair proper mirror
performance.
Do not clean the housing or glass of any mirror with harsh
abrasives, fuel or other petroleum-based cleaning products.
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•They will not reappear until an ignition OFF-ON cycle has been
completed.
This acts as a reminder that these warning conditions still exist within
the vehicle.
Warning display Status
Door Ajar Warning cannot be reset
Coolant over temperature Warning returns after 10 minutes
Powertrain malfunction
Check fuel cap
Check air suspension
Low fuel
Overdrive ON/OFF Warning returns after the ignition key
is turned from OFF to ON.
Trunk ajar
Low tire pressure
Tire pressure monitor fault
Tire pressure sensor fault
Check compass module
Low washer fluid
Change engine oil
DOOR AJAR.Displayed when a door is not completely closed.
POWERTRAIN MALFUNCTION.Displayed when the powertrain is not
operating properly. If the warning stays on or continues to come on,
contact your authorized dealer as soon as possible.
COOLANT OVER TEMPERATURE.Displayed when the engine
coolant is overheating. Stop the vehicle as soon as safely possible, turn
off the engine and let it cool. Check the coolant and coolant level. Refer
toEngine coolantin theMaintenance and Specificationschapter. If
the warning stays on or continues to come on, contact your authorized
dealer as soon as possible.
Never remove the coolant reservoir cap while the engine is
running or hot.
CHECK FUEL CAP.Displayed when the fuel filler cap is not properly
installed. Check the fuel filler cap for proper installation. Refer toFuel
filler capin theMaintenance and Specificationschapter.
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CHECK AIR SUSPENSION.Displayed when the air suspension system
is not operating properly. If this message is displayed while driving, pull
off the road as soon as safely possible. For more information, refer toAir
suspensionin theDrivingchapter.
LOW FUEL.Displayed as an early reminder of a low fuel condition.
Warning message can be reset by pressing the RESET button, but will
return after 10 minutes. If any other button is pressed besides RESET,
the message ’’PRESS RESET TO CLEAR’’ will appear in the Message
Center. Once this message disappears (after approximately 2 seconds),
press RESET to clear the warning.
TRUNK AJAR.Displayed when the trunk is not completely closed.
OVERDRIVE ON/OFF.Displayed when the overdrive is enabled or
disabled.
LOW TIRE PRESSURE.Displayed when one or more tires on your
vehicle have low tire pressure. Refer toInflating Your Tiresin the
Tires, Wheels and Loadingchapter.
TIRE PRESSURE MONITOR FAULT.Displayed when the Tire
Pressure Monitoring System is malfunctioning. If the warning stays on or
continues to come on, have the system inspected by your authorized
dealer.
TIRE PRESSURE SENSOR FAULT.Displayed when a tire pressure
sensor is malfunctioning, or your spare tire is in use (Note: this includes
the use of the optional full-sized matching spare tire and wheel). For
more information on how the system operates under these conditions,
refer toUnderstanding Your Tire Pressure Monitoring Systemin the
Tires, Wheels and Loadingchapter. If the warning stays on or
continues to come on, have the system inspected by your authorized
dealer.
CHECK COMPASS MODULE.Displayed when the compass is not
operating properly. If the warning stays on or continues to come on,
contact your authorized dealer as soon as possible.
LOW WASHER FLUID.Indicates the washer fluid reservoir is less than
one quarter full. Check the washer fluid level. Refer toWindshield
washer fluidin theMaintenance and Specificationschapter.
CHANGE ENGINE OIL.Displayed when the engine oil life remaining is
5 percent or less. When oil life left is between 5% and 0%, the CHANGE
OIL SOON message will be displayed. When oil life left reaches 0%, the
OIL CHANGE REQUIRED message will be displayed.
An oil change is required whenever indicated by the message center and
according to the recommended maintenance schedule. USE ONLY
RECOMMENDED ENGINE OILS.
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The heated seat module resets at every ignition run cycle. While the
ignition is in the ON position, activating the high or low heated seat
switch enables heating mode. When activated, they will turn off
automatically when the ignition is turned to the OFF position.
The indicator light will illuminate when the heated seats have been
activated.
REAR SEATS
Seat mounted cup holders and armrest storage compartment
(if equipped)
Your vehicle may be equipped with
cup holders in the rear seat armrest.
To access the cup holders, fold the
armrest down.
Use only soft cups in the cupholder. Hard objects can injure you
in a collision.
SAFETY RESTRAINTS
Personal Safety System™
The Personal Safety System™ provides an improved overall level of
frontal crash protection to front seat occupants and is designed to help
further reduce the risk of airbag-related injuries. The system is able to
analyze different occupant conditions and crash severity before activating
the appropriate safety devices to help better protect a range of
occupants in a variety of frontal crash situations.
Your vehicle’s Personal Safety System™ consists of the following items:
•Driver and passenger dual-stage airbag supplemental restraints
•Front safety belts with pretensioners, energy management retractors,
and safety belt usage sensors
•Driver’s seat position sensor
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•Front crash severity sensor
•Front passenger sensing system
•“Passenger airbag off” or “pass airbag off” indicator lamp
•Restraints Control Module (RCM) with impact and safing sensors
•Restraint system warning light and back-up tone
•The electrical wiring for the airbags, crash sensor(s), safety belt
pretensioners, front safety belt usage sensors, driver seat position
sensor, front passenger sensing system, and indicator lights.
How does the Personal Safety System™ work?
The Personal Safety System™ can adapt the deployment strategy of your
vehicle’s safety devices according to crash severity and occupant
conditions. A collection of crash and occupant sensors provides
information to the Restraints control module (RCM). During a crash, the
RCM activates the safety belt pretensioners and/or either one or both
stages of the dual-stage airbag supplemental restraints based on crash
severity and occupant conditions.
The fact that the pretensioners or airbags did not activate for both front
seat occupants in a collision does not mean that something is wrong with
the system. Rather, it means the Personal Safety System™ determined
the accident conditions (crash severity, belt usage, etc.) were not
appropriate to activate these safety devices. Front airbags are designed
to activate only in frontal and near-frontal collisions, not rollovers,
side-impacts, or rear-impacts unless the collision causes sufficient
longitudinal deceleration.
Driver and passenger dual-stage airbag supplemental restraints
The dual-stage airbags offer the capability to tailor the level of airbag
inflation energy. A lower, less forceful energy level is provided for more
common, moderate-severity impacts. A higher energy level is used for
the most severe impacts. Refer toAirbag supplemental restraints
section in this chapter.
Front crash severity sensor
The front crash severity sensor enhances the ability to detect the
severity of an impact. Positioned up front, it provides valuable
information early in the crash event on the severity of the impact. This
allows your Personal Safety System™ to distinguish between different
levels of crash severity and modify the deployment strategy of the
dual-stage airbags and safety belt pretensioners.
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Driver’s seat position sensor
The driver’s seat position sensor allows your Personal Safety System™ to
tailor the deployment level of the driver dual-stage airbag based on seat
position. The system is designed to help protect smaller drivers sitting
close to the driver airbag by providing a lower airbag output level.
Front passenger sensing system
For airbags to do their job they must inflate with great force, and this
force can pose a potentially deadly risk to occupants that are very close
to the airbag when it begins to inflate. For some occupants, like infants
in rear-facing child seats, this occurs because they are initially sitting
very close to the airbag. For other occupants, this occurs when the
occupant is not properly restrained by safety belts or child safety seats
and they move forward during pre-crash braking. The most effective way
to reduce the risk of unnecessary injuries is to make sure all occupants
are properly restrained. Accident statistics suggest that children are
much safer when properly restrained in the rear seating positions than in
the front.
Air bags can kill or injure a child in a child seat.NEVERplace a
rear-facing child seat in front of an active air bag. If you must
use a forward-facing child seat in the front seat, move the seat all the
way back.
Always transport children 12 years old and under in the back
seat and always properly use appropriate child restraints.
The front passenger sensing system can automatically turn off the front
passenger airbag and passenger seat-mounted side airbag. The system is
designed to help protect small (child size) occupants from frontal airbag
deployments when they are seated or restrained in the front passenger
seat contrary to proper child-seating or restraint usage
recommendations. Even with this technology, parents areSTRONGLY
encouraged to always properly restrain children in the rear seat. The
sensor also turns off the passenger front airbag when the passenger seat
is empty. The sensor turns off the passenger seat-mounted side airbag (if
equipped) when the seat is empty and the safety belt is unbuckled.
When the front passenger seat is occupied and the sensing system has
turned off the passenger’s frontal airbag, the “pass airbag off” indicator
will light and stay lit to remind you that the front passenger frontal
airbag is off. SeeFront passenger sensing systemin the airbags section
of this chapter.
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Front safety belt usage sensors
The front safety belt usage sensors detect whether or not the driver and
front outboard passenger safety belts are fastened. This information
allows your Personal Safety System™ to tailor the airbag deployment
and safety belt pretensioner activation depending upon safety belt usage.
Refer toSafety beltsection in this chapter.
Front safety belt pretensioners
The safety belt pretensioners at the front outboard seating positions are
designed to tighten the safety belts firmly against the occupant’s body
during frontal collisions and in side collisions. This helps increase the
effectiveness of the safety belts. In frontal collisions, the safety belt
pretensioners can be activated alone or, if the collision is of sufficient
severity, together with the front airbags.
Front safety belt energy management retractors
The front outboard safety belt energy management retractors allow
webbing to be pulled out of the retractor in a gradual and controlled
manner in response to the occupant’s forward momentum. This helps
reduce the risk of force-related injuries to the occupant’s chest by
limiting the load on the occupant. Refer toEnergy management feature
section in this chapter.
Determining if the Personal Safety System™ is operational
The Personal Safety System™ uses a warning light in the instrument
cluster or a back-up tone to indicate the condition of the system. Refer
to theWarning lightsection in theInstrument clusterchapter. Routine
maintenance of the Personal Safety System™ is not required.
The Restraints control module (RCM) monitors its own internal circuits
and the circuits for the airbag supplemental restraints, crash sensor(s),
safety belt pretensioners, front safety belt buckle sensors, front
passenger sensing system, and the driver seat position sensor. In
addition, the RCM also monitors the restraints warning light in the
instrument cluster. A difficulty with the system is indicated by one or
more of the following.
•The warning light will either flash or stay lit.
•The warning light will not illuminate immediately after ignition is
turned on.
•A series of five beeps will be heard. The tone pattern will repeat
periodically until the problem and warning light are repaired.
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Children and airbags
Children must always be properly
restrained. Accident statistics
suggest that children are safer when
properly restrained in the rear
seating positions than in the front
seating position. Failure to follow
these instructions may increase the
risk of injury in a collision.
Airbags can kill or injure a
child in a child seat.
NEVERplace a rear-facing child
seat in front of an active airbag. If
you must use a forward-facing
child seat in the front seat, move
the seat all the way back.
How does the airbag supplemental restraint system work?
The airbag SRS is designed to
activate when the vehicle sustains
longitudinal deceleration sufficient
to cause the sensors to close an
electrical circuit that initiates airbag
inflation.
The fact that the airbags did not
inflate in a collision does not mean
that something is wrong with the
system. Rather, it means the forces
were not of the type sufficient to
cause activation. Driver and passenger airbags are designed to inflate in
frontal and near-frontal collisions, not rollover, side-impact, or
rear-impacts unless the collision causes sufficient longitudinal
deceleration.
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