2008 FORD F150 sensor

Low Tire Pressure
Warning LightPossible cause Customer Action Required
Solid Warning Light Tire(s)
under-inflated1. Check your tire pressure to
ensure tires are properly
inflated; refer toInflating
your tiresin this chapter.
2. After inflating your tires to
the manufacturer’s
recommended inflation
pressure as shown on the Tire
Label (located on the edge of
driver’s door or the B-Pillar),
the vehicle must be driven for
at least two minutes over
20 mph (32 km/h) before the
light will turn OFF.
Spare tire in use Your temporary spare tire is in
use. Repair the damaged road
wheel/tire and reinstall it on
the vehicle to restore system
functionality. For a description
on how the system functions,
refer toWhen your temporary
spare tire is installedin this
section.
TPMS
malfunctionIf your tires are properly
inflated and your spare tire is
not in use and the light
remains ON, have the system
inspected by your authorized
dealer.
Tire rotation
without sensor
trainingOn vehicles with different front
and rear tire pressures, the
TPMS system must be
retrained following every tire
rotation. Refer toTire rotation
in this chapter.
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Owners Guide (post-2002-fmt)
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Please take the tool with the
provided Velcrostrip on the back
and mount it in the bottom right
corner of your Owner’s Guide case
(as shown) for safe keeping.
If you find that the reset tool was
not provided when delivered, has
been lost or no longer functions
(the battery is not replaceable),
please contact your authorized
dealer to obtain a replacement.
To verify that your TPMS reset tool is working, press and release the
button on the center of the TPMS tool. The red light should illuminate
and remain on for approximately five (5) seconds. If the light does not
illuminate, the tool needs to be replaced.
TPMS reset tips
To reduce the chances of interference from another vehicle, TPMS reset
should be performed at least three feet (one meter) away from another
Ford Motor Company vehicle undergoing the TPMS reset procedure at
same time.
Do not wait more than two (2) minutes between resetting each tire
sensor or the system will timeout and the entire procedure will have to
be repeated on all four wheels.
A double horn chirp indicates the need to repeat the procedure.
TPMS reset procedure
Note:It is recommended that you read the entire procedure before
attempting.
Note:To enter the reset mode, Steps 1–5 MUST be completed within 60
seconds.
1. The key must be in the ignition and the ignition turned to OFF/LOCK.
Press and release the brake pedal.
2. Cycle the ignition from OFF/LOCK to RUN three (3) times ending in
the RUN position.DO NOTstart the engine.
3. Press and hold the brake pedal for two (2) seconds, then release.
4. Turn the ignition to OFF/LOCK (DO NOTremove the key.)
5. Cycle the ignition from OFF/LOCK to RUN three (3) times ending in
RUN.DO NOTstart the engine.
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Owners Guide (post-2002-fmt)
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If reset mode has been entered successfully, the horn will sound once,
the TPMS indicator will flash and the message center will displayTRAIN
LF TIRE.
If after repeated attempts to enter reset mode, the horn does not sound,
the TPMS indicator does not flash and the message center does not
display TRAIN LF TIRE, seek service from your authorized dealer.
TPMS reset sequence
The TPMS system needs to be reset starting with the left front tire in
the following clockwise order:
1. Left front tire
2. Right front tire
3. Right rear tire
4. Left rear tire
1.Left front tire:Place the TPMS reset tool against the left front tire
where the tire meets the rim, opposite from the valve stem (1) as shown.
This is where the sensor is located inside the rim.
The tool needs to be held against the tire sidewall opposite the
valve stem as illustrated with the arrow on the tool pointing
towards the rim; do not use the tool with the arrow pointing away
from the rim as it may not activate the sensor.
2. Press and release the green button and hold the tool to the tire
sidewall until the horn sounds. The red light on the TPMS reset tool will
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Owners Guide (post-2002-fmt)
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illuminate while the tool is active. The horn will sound once within
10 seconds to indicate the process was successful.
Note:If a double horn chirp is heard, repeat the procedure. If a single
horn chirp is not heard, move the vehicle to rotate the wheels at least a
1⁄4-turn and repeat the procedure. If the horn does not sound while
attempting to reset any wheel, seek service from your authorized dealer.
3. Perform Steps 1 and 2 on the right front, right rear and finally the left
rear tires.
Successful completion of the reset procedure can be verified by turning
the ignition to OFF without the horn sounding. If two short beeps are
heard, the reset procedure was unsuccessful and must be repeated.
If after repeating the procedure two short beeps are heard when the key
is turned to OFF, seek assistance from your authorized dealer.
Rotation, pressure adjustment and TPMS reset example
The following example describes all the major steps involved in rotating
tires on a vehicle with different front and rear tire pressures. It
illustrates that the TPMS reset procedure needs to follow tire rotation
and pressure adjustment to avoid a possible false low tire warning.
Example:
A particular vehicle has the following recommended tire pressures: 50 psi
(345 kPa) front; 80 psi (552 kPa) rear.
Note:For your vehicle’s pressure, refer to the Safety Compliance
Certification Label located on the B-Pillar or the edge of your vehicle’s
driver’s door.
Before tire rotation
Sensor 1: 50 psi
Sensor 2: 50 psi
Sensor 3: 80 psi
Sensor 4: 80 psi
2008 F-150(f12)
Owners Guide (post-2002-fmt)
USA(fus)
Tires, Wheels and Loading
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Tire rotation using the
recommended sequence
(front tires at top of diagram)
Sensor position following tire
rotation
Sensor 1: 50 psi
Sensor 2: 50 psi
Sensor 3: 80 psi
Sensor 4: 80 psi
Pressure adjustment without the
required TPMS reset procedure
Sensor 1: 80 psi
Sensor 2: 80 psi
Sensor 3: 50 psi
Sensor 4: 50 psi
In this situation, the TPMS warning
light will come on.
If the TPMS reset procedure is not performed after tire rotation and air
pressure adjustment, the TPMS telltale may illuminate for a false low tire
pressure condition.
2008 F-150(f12)
Owners Guide (post-2002-fmt)
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As in this example, the rear tires rotated to the front and properly
inflated to 50 psi (345 kPa) for the front axle would falsely illuminate the
low tire warning indicator as they are still trained for the rear positions
which require 80 psi (552 kPa).
Rotation, pressure adjustment
and successful completion of the
TPMS reset procedure
Sensor 1: 80 psi
Sensor 2: 80 psi
Sensor 3: 50 psi
Sensor 4: 50 psi
Tire rotation and air pressure
adjustment followed by sensor
resetting will ensure the system is properly programmed for vehicles
with different front and rear tire pressures and reduce the risk of a false
low tire warning.
In this situation, the TPMS warning light will be off.
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. 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.
Note: Do not place chains on the following tires sizes: P265/60R18,
P275/65R18, LT275/65R18, P275/55R20, and P275/45R22.
Follow these guidelines when using snow tires and chains:
•Use only SAE Class S chains.
•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.
2008 F-150(f12)
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The RSS automatically turns on
when the gearshift lever is placed in
R (Reverse) and the ignition is ON.
An RSS control allows the driver to
turn the RSS on and off. To turn the
RSS off, the ignition must be ON,
and the gear selector in R
(Reverse). An indicator light on the
control will illuminate when the system is turned off. If the indicator
light illuminates when the RSS is not turned off, it may indicate a failure
in the RSS. The RSS will remain off until either the RSS control is
pushed again or the ignition switch is recycled.
Keep the RSS sensors (located on the rear bumper/fascia) free
from snow, ice and large accumulations of dirt (do not clean the
sensors with sharp objects). If the sensors are covered, it will
affect the accuracy of the RSS.
If your vehicle sustains damage to the rear bumper/fascia, leaving
it misaligned or bent, the sensing zone may be altered causing
inaccurate measurement of obstacles or false alarms.
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Owners Guide (post-2002-fmt)
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Driving
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Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse
Panel Description
F18 10A* Electrochromatic mirror, Heated
seats, BSM, Compass, RSS
(Reverse Sensing System), Power
rail
F19 10A* Restraints (Airbag module)
F20 10A* Power rail
F21 15A* Cluster keep alive power
F22 10A* Delayed accessory power for
audio, power door lock switch and
moon roof switch illumination
F23 10A* RH low beam headlamp
F24 15A* Battery saver power for demand
lamps, Flex fuel
F25 10A* LH low beam headlamp
F26 20A* Horn
F27 5A* Passenger Airbag Deactivation
(PAD) warning lamp, Cluster
airbag warning lamp
F28 5A* SecuriLock transceiver (PATS),
PCM IGN monitor
F29 15A* PCM 4x4 power
F30 15A* PCM 4x4 power
F31 20A* Radio power, Satellite radio
module
F32 15A* Vapor Management Valve (VMV),
A/C clutch relay, Canister vent,
Heated Exhaust Gas Oxygen
(HEGO) sensors #11 and #21,
CMCV, Mass Air Flow (MAF)
sensor, Variable Cam Timing
(VCT), Heated Positive Crankcase
Ventilation (PCV) valve (4.2L
engine), CID sensor (4.2L
engine), 4.6L/4.2L EGR
2008 F-150(f12)
Owners Guide (post-2002-fmt)
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Roadside Emergencies
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