2008 Mercury Grand Marquis sensor

The airbags inflate and deflate
rapidly upon activation. After airbag
deployment, it is normal to notice a
smoke-like, powdery residue or
smell the burnt propellant. This may
consist of cornstarch, talcum
powder (to lubricate the bag) or
sodium compounds (e.g., baking
soda) that result from the
combustion process that inflates the
airbag. Small amounts of sodium
hydroxide may be present which
may irritate the skin and eyes, but
none of the residue is toxic.
While the system is designed to help
reduce serious injuries, contact with
a deploying airbag may also cause abrasions, swelling or temporary
hearing loss. Because airbags must inflate rapidly and with considerable
force, there is the risk of death or serious injuries such as fractures,
facial and eye injuries or internal injuries, particularly to occupants who
are not properly restrained or are otherwise out of position at the time
of airbag deployment. Thus, it is extremely important that occupants be
properly restrained as far away from the airbag module as possible while
maintaining vehicle control.
The SRS consists of the following items:
•Driver and passenger airbag modules (which include the inflators and
airbags)
•safety belt pretensioners
•Front passenger sensing system
•“Passenger airbag off” or “pass airbag off” indicator lamp. Refer to
Front passenger sensing system.later in this chapter.
•Driver and passenger side airbags (if equipped)
•One or more impact and safing sensors
•A readiness light and tone
•A diagnostic module
•The electrical wiring which connects the components
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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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Do not use accessory seat covers. The use of accessory seat
covers may prevent the deployment of the side airbags and
increase the risk of injury in an accident.
Do not lean your head on the door. The side airbag could injure
you as it deploys from the side of the seatback.
Do not attempt to service, repair, or modify the airbag SRS, its
fuses or the seat cover on a seat containing an airbag. See your
authorized dealer.
All occupants of the vehicle should always wear their safety belts
even when an airbag SRS is provided.
How does the side airbag system work?
The design and development of the
side airbag system included
recommended testing procedures
that were developed by a group of
automotive safety experts known as
the Side Airbag Technical Working
Group. These recommended testing
procedures help reduce the risk of
injuries related to the deployment of
side airbags.
The side airbag system consists of
the following:
•An inflatable nylon bag (airbag)
with a gas generator concealed
behind the outboard bolster of
the driver and front passenger
seatbacks.
•A special seat cover designed to allow airbag deployment.
•The same warning light, electronic control and diagnostic unit as used
for the front airbags.
•Two crash sensors located near the side of the vehicle.
Side airbags, in combination with safety belts, can help reduce the risk of
severe injuries in the event of a significant side impact 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.
2008 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
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Seating and Safety Restraints
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When mounting replacement tires and wheels, you should not
exceed the maximum pressure indicated on the sidewall of the
tire to set the beads without additional precautions listed below. If the
beads do not seat at the maximum pressure indicated, re-lubricate and
try again.
When inflating the tire for mounting pressures up to 20 psi greater
than the maximum pressure on the tire sidewall, the following
precautions must be taken to protect the person mounting the tire:
1. Make sure that you have the correct tire and wheel size.
2. Lubricate the tire bead and wheel bead seat area again.
3. Stand at a minimum of 12 feet away from the tire wheel assembly.
4. Use both eye and ear protection.
For a mounting pressure more than 20 psi greater than the maximum
pressure, a Ford Dealer or other tire service professional should do the
mounting.
Always inflate steel carcass tires with a remote air fill with the person
inflating standing at a minimum of 12 ft. away from the tire wheel
assembly.
Important:Remember to replace the wheel valve stems when the road
tires are replaced on your vehicle.
It is recommended that the two front tires or two rear tires generally be
replaced as a pair.
The tire pressure sensors mounted in the wheels (originally installed on
your vehicle) are not designed to be used in aftermarket wheels.
The use of wheels or tires not recommended by Ford Motor Company
may affect the operation of your Tire Pressure Monitoring System.
If the TPMS indicator is flashing, your TPMS is malfunctioning. Your
replacement tire might be incompatible with your TPMS, or some
component of the TPMS may be damaged.
Safety practices
Driving habits have a great deal to do with your tire mileage and safety.
•Observe posted speed limits
•Avoid fast starts, stops and turns
•Avoid potholes and objects on the road
•Do not run over curbs or hit the tire against a curb when parking
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Tires, Wheels and Loading
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The Tire Pressure Monitoring System complies with part 15 of the FCC
rules and with RSS-210 of Industry Canada. Operation is subject to the
following two conditions: (1) This device may not cause harmful
interference, and (2) This device must accept any interference received,
including interference that may cause undesired operation.
The Tire Pressure Monitoring System is NOT a substitute for
manually checking tire pressure. The tire pressure should be
checked periodically (at least monthly) using a tire gauge, see
Inflating your tiresin this chapter. Failure to properly maintain your
tire pressure could increase the risk of tire failure, loss of control,
vehicle rollover and personal injury.
Changing tires with TPMS
Each road tire is equipped with
a tire pressure sensor fastened
to the inside rim of the wheel.
The pressure sensor is covered
by the tire and is not visible
unless the tire is removed. The
pressure sensor is located
opposite (180 degrees) from the
valve stem. Care must be taken
when changing the tire to avoid
damaging the sensor.It is
recommended that you always have
your tires serviced by an authorized
dealer.
The tire pressure should be checked
periodically (at least monthly) using
an accurate tire gauge, refer to
Inflating your tiresin this chapter.
Understanding your Tire Pressure Monitoring System (TPMS)
The Tire Pressure Monitoring System measures pressure in your four
road tires and sends the tire pressure readings to your vehicle. The Low
Tire Warning Lamp will turn ON if the tire pressure is significantly low.
Once the light is illuminated, your tires are under inflated and need to be
inflated to the manufacturer’s recommended tire pressure. Even if the
light turns ON and a short time later turns OFF, your tire pressure still
needs to be checked.
2008 Grand Marquis(grn)
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Tires, Wheels and Loading
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Wheel-speed sensors allow excess rear wheel spin to be detected by the
Traction Control™ portion of the ABS computer. Any excessive wheel
spin is controlled by automatically applying and releasing the rear brakes
in conjunction with engine torque reductions. Engine torque reduction is
realized via the fully electronic spark and fuel injection systems. This
process is very sensitive to driving conditions and very fast acting. The
rear wheels “search” for optimum traction several times a second and
adjustments are made accordingly.
Aggressive driving in any road conditions can cause you to lose
control of your vehicle increasing the risk of severe personal
injury or property damage. The occurrence of an Traction Control™
event is an indication that at least some of the tires have exceeded
their ability to grip the road; this may lead to an increased risk of loss
of vehicle control, vehicle rollover, personal injury and death. If you
experience a severe road event, SLOW DOWN.
The Traction Control™ system will allow your vehicle to make better use
of available traction on slippery surfaces while you are trying to
accelerate or while your foot is on the accelerator pedal. The system is a
driver aid which makes your vehicle easier to handle primarily on snow
and ice covered roads.
During Traction Control™ operation you may hear an electric motor type
of sound coming from the engine compartment and the engine will not
“rev-up” when you push further on the accelerator. This is normal
system behavior.
If you should become stuck in snow
or ice or on a very slippery road
surface, try switching the Traction
Control™ system off. This may
allow excess wheel spin to “dig” the
vehicle out and enable a successful
“rocking” maneuver.
The traction control indicator
flashes during a Traction Control™
system event.
If the traction control indicator
comes on and stays lit, either:
•the Traction Control™ system
requires service by an authorized dealer, or
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Driving
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Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse Panel
Description
1 10A Ignition (START) - Starter relay coil,
DTRS
2 7.5A Power mirrors, Door lock switches,
Mirror switch, Keypad switch, Decklid
switch, Adjustable pedal switch, DDM,
Cluster
3 5A Ignition (START) - Audio mute
4 10A LCM (switch illumination), Autolamp
sensor
5 7.5A Ignition (ON/ACC) - LCM
6 7.5A LCM
7 10A Ignition (ON/ACC) - Wiper module
8 10A Electronic Automatic Temperature
Control (EATC) module (vehicles
equipped with EATC only)
9 7.5A Ignition (ON/ACC) - Door lock switch
illumination, Heated seat switch
illumination, Moon roof, Overhead
console, Radio, Antenna,
Electrochromatic mirror, Window relay
coil
10 15A Hazards
11 15A Ignition (ON) - Turn signals
12 15A Audio
13 10A Ignition (ON) - Anti-lock Brake System
(ABS) module, Rear Air Suspension
Module (RASM), Variable Assist Power
Steering (VAPS), Cluster
14 15A Adjustable pedals
15 10A Ignition (ON) - EATC module, A/C mode
switch (vehicles equipped with manual
A/C only), A/C blower relay coil
16 20A Cigar lighter, OBD II
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Roadside Emergencies
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