O2 sensor TOYOTA CAMRY 2000 Service Repair Manual

1
GENERAL 1999 FEATURES
148BE16
Corolla
Right Side Front
Airbag SensorInflator and Bag for
Front Passenger
(Above the Glove Box)
Airbag Sensor Assembly Inflator and Bag for Driver
(In Steering Wheel Pad) Left Side Front
Airbag Sensor
SRS Warning Light
160GE04
Front Airbag
Sensor (RH)
Battery
Front Airbag
Sensor (LH)
DC-DC
Converter
Back-Up
Power
Source
CPU
Airbag
Sensor
Safing
Sensor
Drive
Circuit
Drive
Circuit
Drive
Circuit
Drive
Circuit
SRS Warning Light
DLC1
Squib (For Driver)
Initiator
(For Front
Passenger)
Spiral Cable
To Seat Belt
Pretensioner Airbag Sensor AssemblyDLC3
5
2. Layout of Components
The major function parts of the airbag systems are shown below.
3. Wiring DIagram

GENERAL 1999 FEATURES
160GE06 160GE05
Normal Condition Activated Condition Stationary
Contact PointRotor
Movable
Contact
PointDeceleration
141BE65 148BO127Corolla
Fig. 1
Fig. 2Range of Operation
Front Airbag
Sensor ON / OFF
Safing Sensor
ON
Airbag Sensor
ONAND
Ignition
6
4. Construction and Operation
Front Airbag Sensor
The front airbag sensor consists of rotor, movable contact point and a stationary contact point.
The rotor is fixed by the initial set load of the movable contact point. At the same time, the movable contact
point restrains the movement of the rotor which is generated during vehicle deceleration, thus preventing
the unintended activation of the system.
If a sudden deceleration that exceeds a predetermined value occurs due to a collision of the vehicle, the rotor
will rotate. The rotational movement of the rotor pushes the movable contact point and causes the movable
and stationary contact points to come into contact. As a result, an ON signal is generated and transmitted
to the airbag sensor assembly.
5. System Operation
Ignition Judgement and Condition
When the vehicle collides in the hatched area (Fig. 1) and the shock is larger than a predetermined level,
the airbag and the seat belt pretensioner are activated automatically. The airbag sensor is characteristically
turned in such a way that can judge the need for ignition in collisions within the hatched area.
The safing sensor is designed to be activated by a smaller deceleration rate than that of the airbag sensor.
As illustrated in Fig. 2 below, ignition is operated when current flows to the squib. This happens when a
safing sensor and the airbag sensor go on simultaneously.
Airbag sensor assembly judges whether or not to inflate the airbag in accordance with ON / OFF of the front
airbag sensor and the deceleration detected by the airbag sensor.

1
GENERAL 1999 FEATURES
156BE19
156BE20 156BE18
Occupant
Detection Sensor
Front Passenger Seat
Land CruiserSpacerElectrode Sheet
Electrode Sheet
Sensor OFF
Occupant
Sensor ON7
SEAT BELT WARNING SYSTEM
1. General
A seat belt warning for the front passenger has been newly provided. When the front passenger seat is occu-
pied but its seat belt is not being worn, this function flashes a warning light to inform the front passenger that
the seat belt is not being worn.
2. Seat Belt Warning for Front Passenger
Construction
The seat belt warning for the front passenger consists of the front passenger seat belt buckle / retractor
switch, occupant detection sensor, seat belt warning light for the front passenger.
1) Belt Warning Occupant Detection Sensor
The occupant detection sensor, which is enclosed in the seat cushion of the front passenger seat, is used
to detect whether or not the front passenger seat is occupied.
This sensor, which is shaped as illustrated below, consists of a construction in which two sheets of elec-
trodes sandwich a spacer. When the occupant is seated, the electrode sheets come in contact with each
other through the hole that is provided in the spacer portion, thus enabling the current to flow.
Thus, the sensor detects whether or not an occupant is seated in the front passenger seat.

GENERAL 1999 FEATURES
156BE14
Warning Light for
Front Passenger
Land Cruiser 8
2) Front Passenger Seat Belt Buckle / Retractor Switch
The front passenger seat belt buckle / retractor switch is enclosed in the seat belt buckle / retractor of the
front passenger seat to detect whether or not the seat belt for the front passenger is being worn.
3) Seat Belt Warning Light for Front Passenger
The seat belt warning light for front passenger flashes to warn if the front passenger does not have the
seat belt buckled.
Operation
When an occupant is seated in the front passenger seat, the occupant detection sensor activates, thus enab-
ling the system to recognize that the occupant has seated. When the ignition switch is turned ON, a warning
light flashes if the front passenger is not wearing the seat belt. The warning light continues to flash until
the front passenger wears the seat belt.
If the front passenger seat is not occupied, the warning light remains extinct regardless of the condition of
the seat belt.

5
CAMRY ± OUTLINE OF NEW FEATURES
160CM05
27
8. Lighting
Daytime running light system with automatic light control sensor is provided on the models for U.S.A. as
optional equipment, and as standard equipment on the models for Canada.
The basic construction and operation are the same as in the '99 Camry Solara.
9. Air Conditioning
An aluminum heater core has been adopted on all models.
A quick joint has been adopted for joining the air conditioner tube.
10.SRS Airbag
A 3-sensor type airbag system has been adopted with the addition of a front airbag sensors, which senses the
impact of a frontal collision. For details, see the General 1999 Features section.
11. Power Seat
A power seat is available as an option for the driver seat on the LE grade model. Also, a power seat is available
as an option for the driver and front passenger seats on the LE grade model with leather seat.
12. Audio
An AM / FM ETR with Cassette Deck and CD Player with built-in power amplifier is available as an option
on the LE grade model.
The pole antenna, which was provided on the CE grade model, has been changed to the rear window im-
printed antenna.
13. Cruise Control System
The cruise control ECU has been made more compact.

INTRODUCTION
INTRODUCTION Ð OUTLINE OF NEW FEATURES3
OUTLINE OF NEW FEATURES
An engine that is based on the 5S-FE engine, yet uses natural gas, has been developed in order to reduce
exhaust emissions and the amount of CO
2 discharge. A model that uses this alternative fuel engine has been
added to the Camry lineup. The characteristics of the new model are listed below.
1. Exterior
A CNG (Compressed Natural Gas) mark is affixed to the luggage compartment door.
2. 5S-FNE Engine
Based on the 5S-FE gasoline engine, the 5S-FNE engine uses compressed natural gas. The fuel lines have
been designed exclusively for compressed natural gas application.
3. A140E Automatic Transaxle
The gear ratio of the differential has been changed to accommodate the performance of the 5S-FNE engine.
4. Brakes
Basically, the same brakes used on the 5S-FE engine model are used on the CNG model, except that the
size of the front brakes has been changed.
5. Suspension
To accommodate the weight increase of the rear section of the vehicle as a result of having the fuel tank
installed in the luggage compartment, the specification of the springs used in the rear suspension has been
changed to realize excellent riding comfort, stability, and controllability.
6. Tire
P205/65 R 15 tire is used.
7. Body

To install the fuel tank in the front area of the luggage compartment, the upper back panel has been
cut out.

A performance rod that joins the tops of the right and left rear suspension strut towers has been adopted.

The shape of the rear floor pan has been changed to prevent the luggage compartment capacity from
being reduced as a result of the installation of the fuel tank in the luggage compartment.
8. Seat
A fixed type seat back is used for the rear seat.
9. Seat Belt
2-point NR (Non-Retractor) seat belt is used for the rear center seat.
10. SRS Airbag
A signal that causes the supply of fuel to be cut off during a frontal collision is output by the airbag sensor
assembly to the ECM.

NEW FEATURES Ð 5S-FNE ENGINE
NEW FEATURES
6
5S-FNE ENGINE
DESCRIPTION
The 5S-FNE engine is a new engine that uses CNG (Compressed Natural Gas) as fuel, which has been
developed based on the 5S-FE gasoline engine.
The main component of natural gas is methane (CH
4), which has fewer carbons (C) than gasoline (mean
molecular formula: C
7.5H13.4). Therefore, the amount of CO2 discharged by this engine is approximately
70% that of the gasoline engine. Furthermore, this engine achieves low-emission operation by precisely
controlled air-fuel ratio and using special catalysts for the CNG application.
However, because the fuel is in the gaseous form, its volumetric efficiency is low, causing lower power
output if this fuel is used in the base engine.
Therefore, the 5S-FNE engine has adopted the following features: a high compression ratio, the intake
valves with early closed timing, the intake and exhaust valves with increased lift, a low back pressure muffler
made possible by the 2-way exhaust system, injectors for gaseous fuel, and a catalytic converter designed
exclusively for CNG application. At the same time, precision air-fuel ratio control is effected through the
use of the air-fuel ratio sensor* and the heater oxygen sensor, thus achieving the level of performance that
is equivalent to the base engine. Moreover, this engine realizes extremely low emissions and restoring engine
torque.
*: Already adopted on the California specification 5S-FE engine.

Specifications 
Item
5S-FNE Engine5S-FE Engine
No. of Cyls. & Arrangement4-Cylinder, In-Line
Valve Mechanism16-Valve DOHC,
Belt & Gear Drive
Combustion CamberPentroof Type
ManifoldsCross-Flow
Fuel SystemSFI
Displacement cm3 (cu. in.)2164 (132.0)
Bore
Stroke mm (in.)87.0
91.0 (3.43
3.58)
Compression Ratio11.0 : 19.5 : 1
Max. Output [SAE-NET]88 kW @ 5200 rpm
(118 HP @ 5200 rpm)
99 kW @ 5200 rpm
(133 HP @ 5200 rpm)
97 kW @ 5200 rpm*
(130 HP @ 5200 rpm)*
Max. Torque [SAE-NET]178 N´m @ 2400 rpm
(131 ft´lbf @ 2400 rpm)
199 N´m @ 4400 rpm
(147 ft´lbf @ 4400 rpm)
197 N´m @ 4400 rpm*
(145 ft´lbf @ 4400 rpm)*
IntakeOpen35 BTDC
Valve
IntakeClose385 ABDC435 ABDCValve
Timing
ExhaustOpen455 BBDCExhaustClose35 AT D C
Fuel Octane Number RON13091
Oil GradeAPI SJ EC or ILSAC
*: California Specification Models

NEW FEATURES Ð 5S-FNE ENGINE 8
FEATURES OF 5S-FNE ENGINE
Features of the 5S-FNE engine are listed below.
Item
Features
Performance
wHigh compression ratio is used.
wHigh lift camshaft is used.
wLow back pressure muffler is used.
Fuel Economy
wHigh compression ratio is used.
wValve spring load has been reduced.
wLow-friction, TiN (titanium nitride) coated valve lifters has been
adopted.
Low Emission
wA fuel injection system containing gas injectors has been adopted.
wBecause the fuel is in the gaseous state, it does not come in contact with
the wall surface, making optimal air-fuel ratio control possible immedi-
ately after the engine has been started.
wPrecision air-fuel ratio feedback control that uses an air-fuel ratio sensor
and a heated oxygen sensor has been adopted.
wTwo catalytic converters designed exclusively for the natural gas engine
have been adopted: the WU-TWC (Warm Up Three-Way Catalytic Con-
verter) and the TWC (Three-Way Catalytic Converter).
Other Features
wHighly rigid pistons have been adopted to accommodate the high com-
pression ratio.
wA CNG (Compressed Natural Gas) pressure regulator that precisely reg-
ulates the CNG has been adopted.
wA large-bore delivery pipe and fuel hose with minimal internal conduit
resistance have been adopted.
wThe electro magnetic fuel shut off valve is added on the delivery pipe.
wA fuel pressure sensor that corrects the fuel injection volume and a fuel
temperature sensor have been provided on the delivery pipe.
wThe starting performance of the engine at low temperatures has been en-
sured by increasing the volume of the airflow of the IAC (Idle Air Con-
trol).
wMaterials that excel in wear resistance have been adopted on the valves
and valve seats for both the intake and exhaust.
wRust-resistant spark plugs have been adopted.
wAluminum lining and carbon fiber have been adopted in the fuel tank.
wFor the fuel gauge, a fuel tank fuel temperature sensor and a fuel pipe fuel
pressure sensor have been adopted.

NF
NEW FEATURES Ð 5S-FNE ENGINE13
FUEL SYSTEM
1. General
The compressed gas [maximum pressure approximately 250 kg/cm2 (3600 psi, 24.8 MPa) @215C (705F)]
from the CNG fuel tank located in the rear section of the vehicle is routed via a fuel filter to the engine
compartment. The pressure of the fuel is then reduced to 8 kg/cm
2 (114 psi, 785 kPa).
A pressure regulator and injectors designed exclusively for CNG application have been adopted.
A fuel pressure sensor and a fuel temperature sensor that are used for the correction of the fuel injection
volume are located on the delivery pipe.
The fuel tank, pressure regulator, and the delivery pipe are provided with shutoff valves that shut off
the fuel when the ignition switch is turned OFF.
In addition, these valves shut off the fuel when the engine stalls, the SRS airbag is deployed, or the
pressure in the main pipe becomes abnormally low.
A fuel temperature sensor for the fuel gauge is mounted on the tank valve assembly, and a fuel pressure
sensor is mounted immediately upstream of the pressure regulator.

Fuel System Diagram 
167CN12
Discharge
Valve
Fuel
Pressure
SensorFuel Temp.
SensorFuel
Pressure
RegulatorFuel Shutoff ValveFuel TankFuel Shutoff Valve
Relief Valve
Inlet Check
Valve
Fuel Temp.
Sensor
Coupler
Tank Valve Assembly
Vent Tube Manual
Shutoff
Valve Fuel
Filter
Fuel
Pressure
Sensor
Fuel Shutoff Valve Injectors
Delivery Pipe

NEW FEATURES Ð 5S-FNE ENGINE 14
2. Fuel Tank
A fuel tank made with carbon fiber and alumi-
num lining has been adopted to prevent weight
increase.
Because the fuel tank expands along with the
increase in the pressure of the compressed gas,
the tank bands contain coil springs to accommo-
date the fluctuation in the perimeter of the tank.
The fuel tank is provided with a tank valve as-
sembly.
3. Tank Valve Assembly
General
The tank valve assembly is mounted on the tank
and consists of a fuel shutoff valve, inlet check
valve, relief valve and two manual cutoff valves.
167CN08
Coil Springs
Tank Valve
AssemblyTank Band
167CN26
Fuel
Temperatur
Sensor
Tank Valve Assembly