2008 Mercury Grand Marquis air condition

•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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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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The diagnostic module monitors its own internal circuits as well as the
supplemental airbag electrical system wiring (including the impact
sensors), the system wiring, the airbag system readiness light, the airbag
back up power and the airbag ignitors.
Several air bag system components get hot after inflation. Do not
touch them after inflation.
If the air bag has deployed,the air bag will not function
again and must be replaced immediately.If the air bag is not
replaced, the unrepaired area will increase the risk of injury in a
collision.
If the safety belt pretensioners deploy in an accident, they will
not function again ( belt will not extract or retract) and must be
replaced immediately. Failure to replace the retractor assemblies will
increase the risk of injury.
Front passenger sensing system
The front passenger sensing system is designed to meet the regulatory
requirements of Federal Motor Vehicle Safety Standard (FMVSS) 208
and is designed to disable (will not inflate) the front passenger’s frontal
airbag under certain conditions.
The front passenger sensing system works with sensors that are part of
the front passenger’s seat and safety belt. The sensors are designed to
detect the presence of a properly seated occupant and determine if the
front passenger’s frontal airbag should be enabled (may inflate) or
disabled (will not inflate).
The front passenger sensing system will disable (will not inflate) the
front passenger’s frontal airbag if:
•the front passenger seat is unoccupied, or has small/medium objects in
the front seat,
•the system determines that an infant is present in a rear-facing infant
seat that is installed according to the manufacturer’s instructions,
•the system determines that a small child is present in a forward-facing
child restraint that is installed according to the manufacturer’s
instructions,
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The front passenger sensing system may detect small or medium objects
placed on the seat cushion. For most objects that are in the front
passenger seat, the passenger airbag will be disabled. Even though the
passenger airbag is disabled, the
pass airbag off
lamp may or may not
be illuminated according to the table below.
ObjectsPass Airbag Off
Indicator LampPassenger Airbag
Small (i.e. 3 ring
binder, small purse,
bottled water)Unlit Disabled
Medium (i.e. heavy
briefcase, fully packed
luggage)Lit Disabled
Empty seat, or small
to medium object with
safety belt buckledLit Disabled
If you think that the status of the passenger airbag off indicator lamp is
incorrect, check for the following:
•Objects lodged underneath the seat
•Objects between the seat cushion and the center console (if
equipped)
•Objects hanging off the seat back
•Objects stowed in the seatback map pocket (if equipped)
•Objects placed on the occupant’s lap
•Cargo interference with the seat
•Other passengers pushing or pulling on the seat
•Rear passenger feet and knees resting or pushing on the seat
The conditions listed above may cause the weight of a properly seated
occupant to be incorrectly interpreted by the front passenger sensing
system. The person in the front passenger seat may appear heavier or
lighter due to the conditions described in the list above.
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An out of position front center occupant could affect the
decision of the front passenger sensing system.
If it is necessary to modify an advanced front airbag system to
accommodate a person with disabilities, contact the Ford Customer
Relationship Center at the phone number shown in theCustomer
Assistancesection of thisOwner’s Guide.
Any alteration/modification to the front passenger seat may
affect the performance of the front passenger sensing system.
Determining if the system is operational
The SRS uses a readiness light in the instrument cluster or a tone to
indicate the condition of the system. Refer toAirbag readinesssection
in theInstrument Clusterchapter. Routine maintenance of the airbag is
not required.
A difficulty with the system is indicated by one or more of the following:
•The readiness light will either
flash or stay lit.
•The readiness 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/or light are repaired.
If any of these things happen, even intermittently, have the SRS serviced
at an authorized dealer immediately. Unless serviced, the system may not
function properly in the event of a collision.
Seat-mounted side airbag system (if equipped)
Do not place objects or mount equipment on or near the airbag
cover on the side of the seatbacks of the front seats or in front
seat areas that may come into contact with a deploying airbag. Failure
to follow these instructions may increase the risk of personal injury in
the event of a collision.
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The side airbags are fitted on the outboard side of the seatbacks of the
front seats. In certain lateral collisions, the airbag on the side affected by
the collision will be inflated. The airbag was designed to inflate between
the door panel and occupant to further enhance the protection provided
occupants in side impact collisions.
The airbag SRS is designed to activate when the vehicle sustains lateral
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. Side airbags are designed
to inflate in side-impact collisions, not roll-over, rear-impact, frontal or
near-frontal collisions, unless the collision causes sufficient lateral
deceleration.
Several air bag system components get hot after inflation. Do not
touch them after inflation.
If the side airbag has
deployed,the airbag will
not function again. The side
airbag system (including the
seat) must be inspected and
serviced by an authorized
dealer.If the airbag is not
replaced, the unrepaired area will
increase the risk of injury in a
collision.
Determining if the system is operational
The SRS uses a readiness light in the instrument cluster or a tone to
indicate the condition of the system. Refer to theAirbag readiness
section in theInstrument Clusterchapter. Routine maintenance of the
side airbag is not required.
A difficulty with the system is indicated by one or more of the following:
•The readiness light (same light as for front airbag system) will either
flash or stay lit.
•The readiness light will not illuminate immediately after ignition is
turned on.
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The traction grade assigned to this tire is based on
straight-ahead braking traction tests, and does not include
acceleration, cornering, hydroplaning or peak traction characteristics.
Temperature A B C
The temperature grades are A (the highest), B and C, representing the
tire’s resistance to the generation of heat and its ability to dissipate heat
when tested under controlled conditions on a specified indoor laboratory
test wheel. Sustained high temperature can cause the material of the tire
to degenerate and reduce tire life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds to a level of performance
which all passenger car tires must meet under the Federal Motor Vehicle
Safety Standard No. 139. Grades B and A represent higher levels of
performance on the laboratory test wheel than the minimum required by
law.
The temperature grade for this tire is established for a tire that
is properly inflated and not overloaded. Excessive speed,
underinflation, or excessive loading, either separately or in
combination, can cause heat buildup and possible tire failure.
TIRES
Tires are designed to give many thousands of miles of service, but they
must be maintained in order to get the maximum benefit from them.
Glossary of tire terminology
•Tire label:A label showing the OE (Original Equipment) tire sizes,
recommended inflation pressure and the maximum weight the vehicle
can carry.
•Tire Identification Number (TIN):A number on the sidewall of
each tire providing information about the tire brand and
manufacturing plant, tire size and date of manufacture. Also referred
to as DOT code.
•Inflation pressure:A measure of the amount of air in a tire.
•Standard load:A class of P-metric or Metric tires designed to carry a
maximum load at 35 psi [37 psi (2.5 bar) for Metric tires]. Increasing
the inflation pressure beyond this pressure will not increase the tire’s
load carrying capability.
•Extra load:A class of P-metric or Metric tires designed to carry a
heavier maximum load at 41 psi [43 psi (2.9 bar) for Metric tires].
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when you get to the pump. It is normal for tires to heat up and the air
pressure inside to go up as you drive.
2. Remove the cap from the valve on one tire, then firmly press the tire
gauge onto the valve and measure the pressure.
3. Add enough air to reach the recommended air pressure.
Note:If you overfill the tire, release air by pushing on the metal stem in
the center of the valve. Then recheck the pressure with your tire gauge.
4. Replace the valve cap.
5. Repeat this procedure for each tire, including the spare.
Note:Some spare tires operate at a higher inflation pressure than the
other tires. For T-type/mini-spare tires (seeDissimilar Spare
Tire/Wheel Informationsection for description): Store and maintain at
60psi (4.15 bar). For Full Size and Dissimilar spare tires (seeDissimilar
Spare Tire/Wheel Informationsection for description): Store and
maintain at the higher of the front and rear inflation pressure as shown
on the Tire Label.
6. Visually inspect the tires to make sure there are no nails or other
objects embedded that could poke a hole in the tire and cause an air
leak.
7. Check the sidewalls to make sure there are no gouges, cuts or bulges.
TIRE CARE
Inspecting your tires
Periodically inspect the tire treads for uneven or excessive wear and
remove objects such as stones, nails or glass that may be wedged in the
tread grooves. Check for holes or cuts that may permit air leakage from
the tire and make necessary repairs. Also inspect the tire sidewalls for
cracking, cuts, bruises and other signs of damage or excessive wear. If
internal damage to the tire is suspected, have the tire demounted and
inspected in case it needs to be repaired or replaced. For your safety,
tires that are damaged or show signs of excessive wear should not be
used because they are more likely to blow out or fail.
Improper or inadequate vehicle maintenance can cause tires to wear
abnormally. Inspect all your tires, including the spare, frequently, and
replace them if one or more of the following conditions exist:
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