2001 NISSAN ALMERA four wheel drive

SEL504X
System DescriptionNJEL0516OUTLINENJEL0516S01The Navigation System (Multi-AV System) relies upon three sens-
ing devices in order to determine vehicle location at regular time
intervals.
1. Vehicle speed sensor: Determines the distance the vehicle has
traveled.
2. Gyro (Angular velocity sensor): Determines vehicle steering
angle and directional change.
3. GPS antenna (GPS data): Determines vehicle forward move-
ment and direction.
The data provided by the three sensing functions together with a
comparison of the mapping information read from the CD-ROM
drive permit accurate determination of the vehicle's current location
and subsequent course (map matching). The information appears
on a liquid crystal display.
This comparison of GPS data (vehicle position sensing) and map
matching permits precise determination of vehicle location.
SEL684V
Position Sensor Operating PrinciplesNJEL0516S0101The sensor determines current vehicle location by calculating the
previously sensed position, the distance traveled from this position,
and the directional changes occurring during this travel.
1. Distance traveled
The distance traveled is calculated using signals received from
the vehicle speed sensor. The sensor automatically compen-
sates for the slightly reduced wheel and tire diameter resulting
from tire wear.
2. Forward movement (Direction)
Changes in the direction of forward movement are calculated
by the gyro (angular velocity sensor) and the GPS antenna
(GPS data). Each of these functions has its advantage and
disadvantages. Depending upon conditions, one function takes
precedence over the other to accurately determine the direc-
tion of forward movement.
Function type Advantage Disadvantage
Gyro (Angular
velocity sen-
sor)+Able to accurately detect
minute changes in steering
angle and direction.+Calculation errors may
accumulate over a long
period of continuous
vehicle travel.
GPS antenna
(GPS data)+Able to sense vehicle travel
in four general directions
(North, South, East, and
West)+Unable to detect direction
of vehicle travel at low
vehicle speeds.
NAVIGATION SYSTEM
System Description
EL-452

SRS443
CAUTION:
+Always place driver air bag module with pad side facing
upward.
+Do not attempt to disassemble driver air bag module.
+The special bolts are coated with bonding agent. Do not
use old bolts after removal; replace with new ones.
+Do not insert any foreign objects (screwdriver, etc.) into
driver air bag module connector.
SBF814E
+Replace driver air bag module if it has been dropped or
sustained an impact.
+Do not expose the driver air bag module to temperatures
exceeding 90ÉC (194ÉF).
+Do not allow oil, grease or water to come in contact with
the driver air bag module.
SBF239F
3. Set steering wheel in the neutral position.
4. Disconnect horn/audio connector and remove nut.
5. Using steering wheel puller, remove steering wheel. Be care-
ful not to over-tighten puller bolt on steering wheel.
CAUTION:
+Do not tap or bump the steering wheel.
6. Remove steering column cover.
SRS384
7. Remove four spiral cable securing screws, and extract spiral
cable forward. Unlock spiral cable connector, then remove spi-
ral cable.
CAUTION:
+Do not attempt to disassemble spiral cable.
+Do not apply lubricant to the spiral cable.
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
Driver Air Bag Module and Spiral Cable (Cont'd)
RS-30

SRS619
CAUTION:
+Always place driver air bag module with pad side facing
upward.
+Do not attempt to disassemble driver air bag module.
+The special bolts are coated with bonding agent. Do not
use old bolts after removal; replace with new ones.
+Do not insert any foreign objects (screwdriver, etc.) into
driver air bag module connector.
SBF814E
+Replace driver air bag module if it has been dropped or
sustained an impact.
+Do not expose the driver air bag module to temperatures
exceeding 90ÉC (194ÉF).
+Do not allow oil, grease or water to come in contact with
the air bag module.
SRS823
4. Set steering wheel in the neutral position.
5. Disconnect horn connector and remove nuts.
6. Using steering wheel puller, remove steering wheel. Be care-
ful not to over-tighten puller bolt on steering wheel.
CAUTION:
+Do not tap or bump the steering wheel.
7. Remove steering column cover.
SRS384
8. Unlock the spiral cable connector. Disconnect connectors and
remove the four screws. The spiral cable can then be removed.
CAUTION:
+Do not attempt to disassemble spiral cable.
+Do not apply lubricant to the spiral cable.
SUPPLEMENTAL RESTRAINT SYSTEM (SRS)
Driver Air Bag Module and Spiral Cable (Cont'd)
RS-33