2003 Mercury Grand Marquis wiring

Your vehicle’s Personal Safety System consists of the following items:
•Driver and passenger dual-stage air bag supplemental restraints
•Driver and front passenger side air bags (if equipped)
•Front safety belts with pretensioners, energy management retractors,
and safety belt usage sensors
•Driver’s seat position sensor
•Passenger occupant classification sensor
•Front crash severity sensor
•Restraints Control Module (RCM) with impact and safing sensors
•Restraint system warning light and back-up tone
•The electrical wiring for the air bags, crash sensor(s), safety belt
pretensioners, front safety belt usage sensors, driver seat position
sensor, passenger occupant classification sensor, 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 air bag supplemental restraints based on crash
severity and occupant conditions.
The fact that the pretensioners or air bags 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 air bags and
pretensioners 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 air bag supplemental restraints
The dual-stage air bags offer the capability to tailor the level of air bag
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 toAir bag 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
2003 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Seating and Safety Restraints
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The air bags inflate and deflate
rapidly upon activation. After air bag
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
air bag. 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 air bag may also cause abrasions, swelling or temporary
hearing loss. Because air bags 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 air bag deployment. Thus, it is extremely important that occupants be
properly restrained as far away from the air bag module as possible while
maintaining vehicle control.
The SRS consists of the following items:
•Driver and passenger air bag modules (which include the inflators and
air bags)
•Driver and passenger side air bags
•One or more impact and safing sensors
•A readiness light and tone
•A diagnostic module
•The electrical wiring which connects the components
The diagnostic module monitors its own internal circuits as well as the
supplemental air bag electrical system warning (including the impact
sensors), the system wiring, the air bag system readiness light, the air
bag back up power and the air bag ignitors.
Several air bag system components get hot after inflation. Do not
touch them after inflation.
2003 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Seating and Safety Restraints
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Driving while you tow
When towing a trailer:
•Turn off the speed control. The speed control may shut off
automatically when you are towing on long, steep grades.
•Consult your local motor vehicle speed regulations for towing a trailer.
•To eliminate excessive shifting, use a lower gear. This will also assist
in transmission cooling. (For additional information, refer to the
Understanding the positions of the 4–speed automatic
transmissionsection in this chapter.
•Anticipate stops and brake gradually.
•Do not exceed the GCWR rating or transmission damage may occur.
Servicing after towing
If you tow a trailer for long distances, your vehicle will require more
frequent service intervals. Refer to your scheduled maintenance guide for
more information.
Trailer towing tips
•Practice turning, stopping and backing up before starting on a trip to
get the feel of the vehicle trailer combination. When turning, make
wider turns so the trailer wheels will clear curbs and other obstacles.
•Allow more distance for stopping with a trailer attached.
•If you are driving down a long or steep hill, shift to a lower gear. Do
not apply the brakes continuously, as they may overheat and become
less effective.
•The trailer tongue weight should be 10–15% of the loaded trailer
weight.
•After you have traveled 80 km (50 miles), thoroughly check your
hitch, electrical connections and trailer wheel lug nuts.
•To aid in engine/transmission cooling and A/C efficiency during hot
weather while stopped in traffic, place the gearshift lever in P (Park).
•Vehicles with trailers should not be parked on a grade. If you must
park on a grade, place wheel chocks under the trailer’s wheels.
Launching or retrieving a boat
Disconnect the wiring to the trailer before backing the trailer
into the water. Reconnect the wiring to the trailer after the
trailer is removed from the water.
2003 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Driving
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When replacing full size tires, never mix radial bias-belted, or
bias-type tires. Use only the tire sizes that are listed on the
Certification or Tire Label. Make sure that all tires are the same size,
speed rating, and load-carrying capacity. Use only the tire combinations
recommended on the label. If you do not follow these precautions,
your vehicle may not drive properly and safely.
Make sure that all replacement tires are of the same size, type,
load-carrying capacity and tread design (e.g., “All Terrain”,
“Touring”, etc.), as originally offered by Ford.
Failure to follow these precautions may adversely affect the
handling of the vehicle, and increase the risk of loss of vehicle
control, vehicle rollover and/or personal injury.
Tires that are larger or smaller than your vehicle’s original tires may also
affect the accuracy of your speedometer.
SNOW TIRES AND CHAINS
Snow tires must be the same size and grade as the tires you
currently have on your vehicle.
The tires on your vehicle have all weather treads to provide traction in
rain and snow. However, in some climates, you may need to use snow
tires and chains.
Follow these guidelines when using snow tires and chains:
•Either cable type chains or SAE class S chains can be used.
•Install chains securely, verifying that the chains do not touch any
wiring, brake lines or fuel lines.
•Drive cautiously. If you hear the chains rub or bang against your
vehicle, stop and re-tighten the chains. If this does not work, remove
the chains to prevent damage to your vehicle.
•If possible, avoid fully loading your vehicle.
•Remove the tire chains when they are no longer needed. Do not use
tire chains on dry roads.
•The suspension insulation and bumpers will help prevent vehicle
damage. Do not remove these components from your vehicle when
using snow tires and chains.
2003 Grand Marquis(grn)
Owners Guide (post-2002-fmt)
USA English(fus)
Maintenance and Specifications
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