
W1841GE 02 MY IMPREZA New Car Information 欧州 Gr. FU T05
CONTROL SYSTEM
Fuel Injection (Fuel System)
FU-4
5. Control System
B: INPUT AND OUTPUT SIGNALS
Signal Unit Function
Pressure sensor Detects the amount of intake air (Measures the absolute pressure).
Mass air flow and intake air tempera-
ture sensor Detects the temperature and amount of intake air.
Throttle position sensor Detects the throttle valve position.
Front oxygen (A/F) sensor Detects the density of oxygen in exhaust gases at the upstream of
the front catalytic converter.
Rear oxygen sensor Detects the density of oxygen in exhaust gases at the downstream
of the rear catalytic converter.
Exhaust gas temperature sensor
(Except STi model) Detects the exhaust gas temperature.
Tumble generator valve position sen-
sor (Except STi model) Detects the tumble generator valve position.
Crankshaft position sensor Detects the crankshaft angular position.
Camshaft position sensor Detects the combustion cylinder.
Input signals Variable valve timing camshaft posi-
tion sensor (Only STi model) Detects amounts of advance and retard angles of the intake valves.
Engine coolant temperature sensor Detects the engine coolant temperature.
Knock sensor Detects engine knocking.
Vehicle speed sensor Detects the vehicle speed.
Ignition switch Detects operation of the ignition switch.
Starter switch Detects the condition of engine cranking.
Neutral position switch Detects that the gear is in neutral.
Heater circuit of front and rear oxy-
gen sensor
Detects the abnormality in heater circuit of front and rear oxygen
sensor.
A/C switch Detects ON-OFF operation of the A/C switch.
Fuel level sensor Detects the level of the fuel in the fuel tank.
Small light switch Detects ON-OFF operation of the small light switch.
Blower fan switch Detects ON-OFF operation of the blower fan switch.
Rear defogger switch Detects ON-OFF operation of the rear defogger switch.
Fuel Injector Activates an injector.
Ignition signal Turns the primary ignition current ON or OFF.
Fuel pump controller Controls the fuel pump.
A/C control relay Turns the A/C control relay ON or OFF.
Radiator fan control relay Turns the radiator fan control relay ON or OFF.
Idle air control solenoid valve Adjusts the amount of air flowing through the bypass line in the
throttle body.
Output signals Tumble generator valve actuator
(Except STi model) Operates the tumble generator valve.
Wastegate control solenoid valve Controls supercharging pressure
Malfunction indicator lamp Indicates existence of abnormality.
Purge control solenoid valve Controls purge of evaporative gas absorbed by the canister.
Power supply Controls ON/OFF of the main power supply relay.
Variable valve timing solenoid valve
(Only STi model) Controls advance and retard angles of the intake valves.