2000 TOYOTA CAMRY ignition

CAMRY ± NEW FEATURES
150NF111
SRS Warning
LightAirbag Sensor
AssemblyRight Side Airbag
Assembly
Right Side Airbag
Sensor Assembly
Left Side Airbag
Sensor Assembly Left Side
Airbag Assembly
150NF112
BatterySide Airbag Sensor
Assembly (LH)
Initiator
(LH)
Back-Up
Power Source
DC-DC
Converter
CPU
Airbag Sensor AssemblyInitiator
(RH) Side Airbag Sensor
Assembly (RH)
SRS Warning Light
Drive
Circuit
Communication
Circuit
Drive
CircuitSafing
Sensor
Drive
Circuit
Drive
Circuit
DLC1
Power
Control
Ignition Switch
Communication
Circuit
Power
Control
18
2. Layout of Components
The major function parts of the side airbag system are shown below.
3. Wiring Diagram

CAMRY ± NEW FEATURES19
4. Construction and Operation
Side Airbag Sensor Assembly
1) Description
The side airbag sensor assembly is mounted on the right and left center pillars. It receives signals from
the side airbag sensor enclosed in the side airbag sensor assembly and judges whether the side airbag must
be activated or not.
2) Construction and Operation
The side airbag sensor assembly consists of side airbag sensor, safing sensor, etc.
a. Side Airbag Sensor
The side airbag sensor is enclosed in the side airbag sensor assembly based on the acceleration of the
vehicle that occurs during a side collision. The distortion created in the sensor is converted into an elec-
tric signal. This signal is a linear representation of the acceleration rate.
b. Safing Sensor
The safing sensor is enclosed in the side airbag sensor assembly. The sensor turns ON if an acceleration
force that is higher than a predetermined value is applied to the safing sensor as a result of a side colli-
sion.
Airbag Sensor Assembly
1) Description
The airbag sensor assembly is mounted on the center floor under the instrument panel.
When the airbag sensor assembly receives the airbag activation signal from the side airbag sensor assem-
bly, it applies current to the inflator.
Furthermore, the airbag sensor assembly diagnoses a system malfunction of the side airbag system.
This is the same airbag sensor assembly that is used for the
SRS airbag for the driver and front passenger.
2) Construction and Operation
The airbag sensor assembly consists of ignition control circuit, back up power source, diagnosis circuit,
memory circuit, etc.
a. Ignition Control Circuit
The ignition control circuit performs a prescribed calculation based on the signal output by the airbag
sensor and the front airbag sensor. If these calculated values are larger than a predetermined value, it
activates the ignition operation.
b. Back-Up Power Source
The back-up power source consists of a back-up capacitor and a DC-DC converter. In case of a power
system failure during a collision, the back-up capacitor discharges and supplies electric power to the
system. The DC-DC converter is a boosting transformer when the battery voltage drops below a certain
level.
c. Diagnosis Circuit
This circuit constantly diagnoses the system for any malfunction. When a malfunction is detected, it
lights up the
SRS warning light on the combination meter to alert the driver.
d. Memory Circuit
When a malfunction is detected by the diagnosis circuit, it is coded and stored in this memory circuit.

CAMRY ± NEW FEATURES
150NF113
SRS Warning Light
150NF114
Range of Operation
Safing
Sensor ON
Side Airbag
Sensor ON
ANDIgnition
21
SRS Warning Light
The
SRS warning light is located on the
combination meter.
It comes on to alert the driver about system
trouble when a malfunction is detected in
self-diagnosis of the airbag sensor assembly and
side airbag sensor assembly. In normal operating
conditions when the ignition switch is turned to
the ACC or ON position, the light comes on for
about 6 seconds and then goes off.
5. System Operation
Ignition Judgement and Conditions
The safing sensor is designed to be activated by a smaller acceleration rate than the side airbag sensor.
As illustrated below, ignition is caused when current flows to the initiator, which happens when a safing
sensor and the side airbag sensor go on simultaneously.

CAMRY ± NEW FEATURES
150NF116
Transponder Chip
Ignition KeyTransponder
Key Coil
Key
Cylinder
Transponder
Key AmplifierECMSpark Plug
Injector
150NF117
Transponder Key
AmplifierTransponder Key Coil
ECM
23
ENGINE IMMOBILISER SYSTEM
1. General
The engine immobiliser system is a theft-deterrent system which disables the engine from starting using the
ignition key with an ID code that matches is the pre-registered code in the vehicle.
This system adopts a transponder system which uses a transponder chip embedded in the grip of the ignition
key. When the coil located around the ignition key cylinder receives the ID code signal transmitted by the
transponder chip, the computer included in the ECM determines whether or not the ID code matches the code
stored in the computer.

System Diagram 
2. Layout of Components
The major function parts of the engine immobiliser system are shown below.

CAMRY ± NEW FEATURES
150NF118
BatteryIgnition Switch
EFI
Relay
Transponder
Key Coil
Transponder
Key AmplifierECMBody
ECU
DLC1
150NF119
Transponder Chip
24
3. Wiring Diagram
4. Construction
The engine immobiliser system consists of the transponder key (ignition key), transponder key coil, trans-
ponder key amplifier, and ECM.
Transponder Key (Ignition Key)
A transponder chip is embedded in the grip of the
ignition key. Each transponder chip contains an
individual transponder key-code (ID code). The
key does not need an internal battery to transmit
a key code.
Transponder Key Coil and Transponder Key Amplifier
The transponder key coil is a ring-shaped coil installed around the ignition key cylinder. The transponder
key amplifier is installed in the back of the key cylinder.
An electrical power circuit to provide power to the transponder key coil has been enclosed in the amplifier.
ECM
The control circuit of the engine immobiliser system has been integrated inside the ECM. As a result, the
time has been reduced taken for the engine to start in case of mismatching key code thus improving the
system's theft deterrent performance.
A maximum of 10 different transponder key codes (master key: 7 types, sub key: 3 types) can be registered
in the ECM.

CAMRY ± NEW FEATURES
150NF120
Ignition KeyElectromagnetic
Energy
Transponder
ChipKey-Code
SignalTransponder Key
AmplifierECM
150NF121
Key-Code
SignalKey-Code
Transponder
Key AmplifierKey-CodeCode Memory Circuit
Code
Comparison
Circuit
ECMSpark Plug
Injector25
5. Operation
Setting the Engine Immobiliser System
When the ignition key is removed from the key cylinder, the engine immobiliser system will be set.
Unsetting the Engine Immobiliser System
1
When the ignition key is inserted in the key cylinder, the ECM instructs the transponder key coil to sup-
ply the electromagnetic energy that enables the transponder chip to transmit a key-code signal. The
transponder chip then uses this electrical energy to transmit a key-code signal.
2
The key-code signal that has been received at the coil is amplified by the transponder key amplifier and
sent to the ECM. The key-code that has been received by the ECM is then compared to the key-code
that is stored in the ECM. The code comparison process takes place and if the codes match in a row,
the ECM unsets the immobiliser system. As a result, the engine will be able to start.

CAMRY ± NEW FEATURES 26
6. Functions
The engine immobiliser system provides the following functions:
Immobiliser Cancel Function
The immobiliser system is cancelled when the following condition is met, thus permitting authorized opera-
tion of the engine:
The ignition key has been inserted in the key cylinder (after the ECM reads the key code of the transpond-
er chip and that code matches the pre-registered key code).
New Transponder Key Code Registration Function
This function allows the registration of the key code of two master keys and a sub key to the new ECM. This
function is used if the ECM is replaced with a new one.
Additional Transponder Key Code Registration Function
This function enables the registration of the key code for a new master key or sub key, while retaining the
key codes that are already registered. This function is used for the purpose of adding a new master or sub
key. A maximum of 10 different transponder key codes (7 for master keys and 3 for sub keys) can be regis-
tered in the ECM.
Transponder Key Code Delete Function
This function deletes all the transponder key codes that are registered in the ECM except for the key code
of the master key that was used to execute the delete function.
For further details on transponder key code registration, addition, and deletion, see the 1998 Camry Repair
Manual (Pub. No. RM589U).
Appendix

'99camry U
3
1. Power rear view mirror control switch
2. Headlight and turn signal switch
3. Wiper and washer switches
4. Clock
5. Emergency flasher switch
6. Car audio
7. Rear window and outside rear view
mirror defoggers switch
8. Air conditioning controls
9. Front ashtray
10. Power outlet
11. Cigarette lighter
12. Ignition switch
13. Cruise control switch
14. Tilt steering lock release lever
15. Traction control system off switch
16. Instrument panel light control knob