2009 Mercury Grand Marquis wiring

•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 Systemwork?
The Personal Safety Systemcan 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 may activate 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 Systemdetermined
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
(SRS)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 Systemto distinguish between different
levels of crash severity and modify the deployment strategy of the
dual-stage airbags and safety belt pretensioners.
Driver’s seat position sensor
The driver’s seat position sensor allows your Personal Safety Systemto
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.
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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 systemlater in this chapter.
•Driver and passenger side airbags
•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 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.
WARNING:Several air bag system components get hot after
inflation. Do not touch them after inflation.
WARNING: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.
WARNING: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.
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any tire is under-inflated, carefully drive the vehicle to the nearest
location where air can be added to the tires. Inflate all the tires to the
recommended inflation pressure.
SNOW TIRES AND CHAINS
WARNING:Snow tires must be the same size, load index, speed
rating as those originally provided by Ford. Use of any tire or
wheel not recommended by Ford can affect the safety and
performance of your vehicle, which could result in an increased risk of
loss of vehicle control, vehicle rollover, personal injury and death.
Additionally, the use of non-recommended tires and wheels could
cause steering, suspension, axle or transfer case/power transfer unit
failure.
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. If you need to use chains, it is recommended that steel
wheels (of the same size and specifications) be used, as chains may chip
aluminum wheels.
Follow these guidelines when using snow tires and chains:
•Use only cable type chains offered by Ford Motor Company as an
accessory or equivalent. Using SAE class S or other conventional link
type chains may cause damage to the vehicle’s wheel house and/or
body.
•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.
•Do not exceed 30 mph (48 km/h) with tire cables on your vehicle.
VEHICLE LOADING – WITH AND WITHOUT A TRAILER
This section will guide you in the proper loading of your vehicle and/or
trailer, to keep your loaded vehicle weight within its design rating
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•After you have traveled 50 miles (80 km), 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.
When backing down a ramp during boat launching or retrieval:
•do not allow the static water level to rise above the bottom edge of
the rear bumper.
•do not allow waves to break higher than 6 inches (15 cm) above the
bottom edge of the rear bumper.
Exceeding these limits may allow water to enter vehicle components:
•causing internal damage to the components.
•affecting driveability, emissions and reliability.
Replace the rear axle lubricant any time the axle has been submerged in
water. Rear axle lubricant quantities are not to be checked or changed
unless a leak is suspected or repair required.
RECREATIONAL TOWING
Follow these guidelines if you have a need for recreational (RV) towing.
An example of recreational towing would be towing your vehicle behind
a motorhome. These guidelines are designed to ensure that your
transmission is not damaged.
All vehicles:Do not tow your vehicle with any wheels on the ground, as
vehicle or transmission damage may occur. It is recommended to tow
your vehicle with all four (4) wheels off the ground such as when using a
car-hauling trailer. Otherwise, no recreational towing is permitted.
In case of a roadside emergency with a disabled vehicle, seeWrecker
towingin theRoadside Emergencieschapter.
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