Toyota 2007 CAMRY Manual page 122

2. Control System
∗ SFI system
The SFI system monitors the engine condition through the signals input from each sensors to the engine control module.
The control signal is sent to the engine control module TERMINALS #10, #20, #30, #40, #50 and #60 to operate the
injector (Fuel injection). The SFI system controls the fuel injection by the engine control module in response to the driving
conditions.
∗ ESA system
The ESA system monitors the engine condition through the signals input from each sensors to the engine control module.
The best ignition timing is decided according to this data and the data memorized in the engine control module. The
control signal is output to TERMINALS IGT1, IGT2, IGT3, IGT4, IGT5 and IGT6, and these signals control the igniter to
provide the best ignition timing.
∗ Heated oxygen sensor heater control system
The heated oxygen sensor heater control system turns the heater on when the intake air volume is low (Temp. of exhaust
emission is low), and warms up the heated oxygen sensors to improve their detection performance. The engine control
module evaluates the signals from each sensors, and outputs current to TERMINALS HT1B or HT2B to control the heater.
∗ Air fuel ratio sensor heater control system
The air fuel ratio sensor heater control system turns the heater on when the intake air volume is low (Temp. of exhaust
emission is low), and warms up the air fuel ratio sensor to improve detection performance of the sensor.
The engine control module evaluates the signals from each sensor, current is output to TERMINALS HA1A and HA2A,
controlling the heater.
∗ ACIS
The ACIS includes a valve in the bulkhead separating the surge tank into two parts. This valve is opened and closed in
accordance with the driving conditions to control the intake manifold length in two stages, for increased engine output in all
ranges from low to high speeds.
∗ ETCS–i
The ETCS–i controls the engine output at its optimal level in accordance with the opening of the accelerator pedal, under
all driving conditions.
∗ Dual VVT–i
Dual VVT–i controls the intake and exhaust valve timing to the most appropriate levels in accordance with the engine
conditions.
3. Diagnosis System
When there is a malfunction in the engine control module signal system, the malfunctioning system is recorded in the
memory. The malfunctioning system can be found by reading the code displayed on the malfunction indicator lamp.
4. Fail–Safe System
When a malfunction has occurred in any system, there is a possibility of causing engine trouble due to continued control
based on that system. In that case, the fail–safe system either controls the system using the data (Standard values)
recorded in the engine control module memory, or else stops the engine.
CAMRY (EM0250U)
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