1999 FORD F150 sensor

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, it may also
cause minor burns, 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.
Several air bag system components get hot after inflation. Do not
touch them after inflation.
If the air bag is inflated,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.
The SRS consists of:
²driver and passenger air bag modules (which include the inflators and
air bags),
²one or more impact and safing sensors, passenger air bag deactivation
switch and diagnostic monitor (RCM)
²a readiness light and tone
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²and the electrical wiring which connects the components.
The RCM (restraints control module) monitors its own internal circuits
and the supplemental air bag electrical system warning (including the
passenger air bag deactivation switch, the impact sensors, the system
wiring, the air bag system readiness light, the air bag back up power and
the air bag ignitors).
Determining if the system is operational
The SRS uses readiness lights in the instrument cluster and the
passenger air bag deactivate switch or a tone to indicate the condition of
the system. Refer to theAir bag readinesssection in the
Instrumentationchapter orPassenger air bag deactivate switch
section in this chapter. Routine maintenance of the air bag is not
required.
A difficulty with the system is indicated by one or more of the following:
²The readiness lights will either
flash or stay lit.
²The readiness lights will not
illuminate immediately after
ignition is turned on.
²A series of five beeps will be heard. The tone pattern will repeat
periodically until the problem and light are repaired.
If any of these things happen, even intermittently, have the SRS serviced
at your dealership or by a qualified technician immediately. Unless
serviced, the system may not function properly in the event of a
collision.
Disposal of air bags and air bag equipped vehicles
For disposal of air bags or air bag equipped vehicles, see your local
dealership or qualified technician. Air bags MUST BE disposed of by
qualified personnel.
Seating and safety restraints
98

The high-current fuses are coded as follows.
Fuse/Relay
LocationFuse Amp
RatingDescription
1 25A * Power Point
2 30A* Powertrain Control Module
3 30A* Headlamps/Autolamps
4 15A* Air Suspension
5 20A* Trailer Tow Backup/Park Lamps
6 15A* Parklamps/Autolamps
7 20A* Horn
8 15A* Power Door Locks
9 15A* Daytime Running Lamps (DRL), Fog Lamps
10 20A* Fuel Pump
11 20A* Alternator Field
12 Ð Not Used
13 Ð Not Used
14 Ð Not Used
15 Ð Not Used
16 Ð Not Used
17 Ð Not Used
18 15A* Powertrain Control Module, Fuel Injectors,
Fuel Pump, Mass Air Flow Sensor
19 10A* Trailer Tow Stop and Right Turn Lamp
20 10A* Trailer Tow Stop and Left Turn Lamp
21 Ð Not Used
22 Ð Not Used
23 15A* Powertrain Control Module, HEGO Sensor,
Canister Vent
24 15A* Powertrain C ontrol Module, Automatic
Transmission, CMS Sensor
101 30A** Trailer Tow Battery Charge
102 50/20A** Four Wheel Antilock Brake Module/Rear
Wheel Antilock Brake Module
Roadside emergencies
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