ignition CHEVROLET IMPALA 2001 8.G Manual PDF

6-43 Tire Inflation Monitor System
(If Equipped)
The tire inflation monitor system can alert you to a large
change in the pressure of one tire. The system ªlearnsº
the pressure at each tire throughout the operating speed
range of your vehicle. The system normally takes
between 45 and 90 minutes of driving to learn the
tire pressures. This time may be longer depending on
your individual driving habits. Learning need not be
accumulated during a single trip. Once learned, the
system will remember the tire pressures until the
system is recalibrated.
After the system has learned tire pressures with properly
inflated tires, the LOW TIRE PRESSURE message
will come on if the pressure in one tire becomes
12 psi (83 kPa) lower than the other three tires.
The tire inflation monitor system won't alert you if the
pressure in more than one tire is low, if the system is
not properly calibrated, or if the vehicle is moving faster
than 70 mph (110 km/h).
The tire inflation monitor system detects differences
in tire rotation speeds that are caused by changes in
tire pressure. The system can alert you about a low
tire
-- but it doesn't replace normal tire maintenance.
See ªTiresº in the Index.When the LOW TIRE PRESSURE message comes on,
you should stop as soon as you can and check all your
tires for damage. (If a tire is flat, see ªIf a Tire Goes
Flatº in the Index.) Also check the tire pressure in all
four tires as soon as you can. See ªInflation
- Tire
Pressureº in the Index.
The LOW TIRE PRESSURE message will also be
displayed (while the ignition is on) until you reset
(calibrate) the system.
Don't reset the tire inflation monitor system without first
correcting the cause of the problem and checking and
adjusting the pressure in all four tires. If you reset the
system when the tire pressures are incorrect, the system
will not work properly and may not alert you when a
tire is low.
Any time you adjust a tire's pressure, rotate your tires,
or have one or more tires repaired or replaced, you'll
need to reset (calibrate) the tire inflation monitor
system. You'll also need to reset the system whenever
you buy new tires and whenever the vehicle's battery
has been disconnected.

6-44
To reset (calibrate) the system: The tire inflation
monitor system can be reset by turning the exterior lamp
control from OFF to parking lamps three times while the
ignition is in ON. It can also be reset through the RDS
radio (if equipped) using the following steps:
1. Turn the ignition to ACC or ON and turn the
radio off.
2. Press and hold the DISP button on the radio for at
least five seconds until SETTINGS is displayed.
3. Press the SEEK up or down arrow to scroll through
the main menu.
4. Scroll until TIRE MON appears on the display.
5. Press the PREV or NEXT button to enter the
submenu. RESET will be displayed.
6. Press the DISP button to reset. A chime will be heard
to verify the new setting and DONE will be
displayed for one second.
7. Once the monitor has been reset, scroll until EXIT
appears on the display.
8. Press the DISP button to exit programming.
A chime will be heard to verify exit.
The system completes the calibration process
during driving.The system normally takes 15 to 20 minutes of driving
in each of three speed ranges to ªlearnº tire pressures.
The speed ranges are 15 to 40 mph (25 to 65 km/h),
40 to 65 mph (65 to 105 km/h) and above 65 mph
(105 km/h). When learning is complete, the system will
alert you after 2
-8 minutes if a tire is 12 psi (83 kPa)
different from the other three tires. Detection thresholds
may be higher and detection times may be longer on
rough roads, curves and at high speeds. The system
is not capable of detection at speeds greater than
70 mph (110 km/h).
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
(10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires as soon as possible and check
wheel alignment. Also check for damaged tires or
wheels. See ªWhen It's Time for New Tiresº and
ªWheel Replacementº later in this section for
more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The first
rotation is the most important. See ªScheduled
Maintenance Servicesº in the Index for scheduled
rotation intervals.

6-62
Circuit
BreakerDescription
RETAINED
ACCESSORY
PWR BRKRPower Window, Sunroof Breaker
Mini Fuses Description
PCM/BCM/
CLSTRPowertrain Control Module,
Body Control Module, Cluster
(Ignition 0)
WSW Windshield Wipers,
Windshield Washer
PCM (CRANK) Powertrain Control
Module (Crank)
CIG/AUX Accommodated
Device (Accessory)
BCM Body Control Module (Accessory)
SRS Supplemental Restraint System
ABS/PCM Anti
-Lock Brake System,
Powertrain Control Module, Brake
Switch, Crank Relay, Canister Vent
Solenoid (Run, Crank)Mini Fuses Description
STOP Brake Lamps, Body Control
Module (Run, Crank)
TURN SIGNAL Turn Signal Flashers
CRUISE Cruise Control Steering
Column Controls
A/C/CRUISE HVAC Temp Door Motors &
Module, Cruise Control Module
A/C FAN HVAC Blower
STR COL Steering Wheel Lighting
DR LK Body Control Module,
Door Lock Controls
PWR MIR Power Mirrors
CLSTR/BCM Cluster, Body Control Module,
Data Link Connector (Battery)
LH HTD
ST/BCMDriver's Heated Seat, Body
Control Module, Battery
Controlled Loads

6-66
Underhood Fuse Block (Lower)
Some fuses are in a fuse block on the passenger's side of
the engine compartment. See ªEngine Compartment
Overviewº in the Index for more information on location.
Circuit Relay Description
FAN CONT #3 Secondary Cooling Fan
(Passenger's Side)
FAN CONT #2 Cooling Fan Control Relay
FAN CONT #1 Primary Cooling Fan
(Driver's Side)Circuit Relay Description
IGN RELAY Ignition Relay
A/C CMPR HVAC Compressor
Maxi Fuses Description
IGN SW Ignition Switch
RT I/P #3 Rear Defogger, Audio System
U/HOOD #2 Ignition Relay, AIR Pump
COOLING
FANSCooling Fans (Battery)
Mini Fuses Description
FAN
CONT #2 & #3Cooling Fan Control
Relays #2 & #3
FAN CONT #1 Cooling Fan Control Relays #1
AIR PMP RLY Air Induction Reaction Pump
Relay (Battery)
FUEL INJ Fuel Injectors
TRANS SOL Transmission Solenoids
A/C RLY
(COIL)HVAC Control Relay
ENG DEVICES Canister Purge Solenoid, Mass Air
Flow Sensor (MAF), AIR Pump
Relay & Valve Control
DFI MDL Direct Fire Ignition Module
OXY SEN Oxygen Sensors
(Pre and Post Converter)

7-18
Ignition Transaxle Lock Check
While parked, and with the parking brake set, try to turn
the ignition key to OFF in each shift lever position.

The key should turn to OFF only when the shift lever
is in PARK (P).

The key should come out only in OFF.
Parking Brake and Automatic Transaxle PARK (P)
Mechanism Check
CAUTION:
When you are doing this check, your vehicle
could begin to move. You or others could be
injured and property could be damaged. Make
sure there is room in front of your vehicle in case
it begins to roll. Be ready to apply the regular
brake at once should the vehicle begin to move.
Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot on the regular brake,
set the parking brake.

To check the parking brake's holding ability: With
the engine running and transaxle in NEUTRAL (N),
slowly remove foot pressure from the regular brake
pedal. Do this until the vehicle is held by the parking
brake only.

To check the PARK (P) mechanism's holding ability:
With the engine running, shift to PARK (P).
Then release the parking brake followed by the
regular brake.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care to
clean thoroughly any areas where mud and other debris
can collect.