Toyota COROLLA2004, Electrical Wiring Diagram

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2004 COROLLA (EWD533U)
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Engine Control
2. Control System
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SFI system
The SFI system monitors the engine conditions through the signals, which are input from each sensor to the engine
control module. Based on this data and the program memorized in the engine control module, the most appropriate fuel
injection timing is decided and current is output to TERMINALS #10, #20, #30 and #40 of the engine control module,
operating the injectors (to inject fuel). This is the system which finely controls the fuel injection in response to the driving
conditions, through the engine control module.
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ESA system
The ESA system monitors the engine conditions using the signals, which are input to the engine control module from each
sensor. Based on this data and the program memorized in the engine control module, the most appropriate ignition timing
is decided and current is output to TERMINALS IGT1, IGT2, IGT3 and IGT4 of the engine control module. This output
controls the ignition coil and igniter No. 1 , No. 2 , No. 3 and No. 4 to produce the most appropriate ignition timing for the
driving conditions.
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IAC system
The IAC system increases the RPM and provides idle stability for fast idle–up when the engine is cold, and when the idle
speed has dropped due to electrical load and so on. The engine control module evaluates the signals from each sensor,
and outputs current to TERMINAL RSO to control the idle air control valve.
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Knock control system
Knock control system controls the gate based on the engine rotation speed and detects knocking by the peak value of the
knock sensor output during the gate open period, and then controls it to the most suitable ignition timing in proportion to
the driving condition.
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Evapoparge control system
This system leads the vapor stuck to the canister to the serge tank in order not to agitate the air fuel by adjusting the fuel
injection volume.
The signal at this time will be output from TERMINAL EVP of the engine control module to VSV (EVAP).
3. Diagnosis System
With the diagnosis system, when there is a malfunctioning in the engine control module signal system,the malfunction
system is recorded in the memory. The malfunctioning system can be found by reading the display (Code) of the malfunction
indicator lamp.
4. Fail–Safe System
When a malfunction occurs in any system, if there is a possibility of engine trouble being caused by continued control based
on the signals from that system, the fail–safe system either controls the system by using the data (Standard values)
recorded in the engine control module memory or else stops the engine.