Content .. 7 8 9 10 ..

Mitsubishi Lancer Evolution 7. Manual - part 9

ENGINE -

Control System

1-15

CONTROL SYSTEM DIAGRAM

1 Oxygen sensor (front)

2 Oxygen sensor (rear)

3 Air flow sensor

4 Intake air temperature sensor

5 Throttle position sensor

6 Camshaft position sensor

7 Crank angle sensor

8 Barometric pressure sensor

9 Engine coolant temperature sensor

10 Detonation sensor

1 Injector

2 Idle speed control servo

3 Fuel pressure control solenoid valve

4 Waste gate solenoid valve

5 EGR control solenoid valve

6 Purge control solenoid valve

7 Secondary air control solenoid valve

Power supply

Ignition switch-IG

Ignition switch-ST

Vehicle speed sensor

A/C switch

A/C l

oad signal

Power steering fluid pressure switch

Alternator FR terminal

Engine control relay

Fuel pump relay 2, 3

A/C relay

Ignition coil

Fan controller

Condenser fan relay (HI)

Condenser fan relay (LOW)

Engine warning lamp

Diagnosis output

Alternator G terminal

Engine-ECU

1 Oxygen

sensor

(front)

4 Intake air

temperature

sensor

5 Throttle

position

sensor

6 Camshaft

position sensor

1 Injector

2 Idle

speed

control

servo

6 Purge

control

solenoid

valve

Three-way

catalytic converter

Canister

Air

inlet

Vacuum

tank

Fuel

pressure

regurator

From

fuel tank

To fuel tank

PCV valve

From

fuel pump

Waste gate

actuator

2 Oxygen sensor (rear)

Check

valve

By-pass

valve

5 EGR control

solenoid valve

4 Waste gate

solenoid valve

8 Barometric

pressure

sensor

3 Air flow

sensor

7 Secondary

air control

solenoid

valve

Secondary

air valve

3 Fuel pressure

control

solenoid valve

EGR

valve

9 Engine coolant

temperature sensor

7 Crank angle sensor

10 Detonation sensor

ENGINE -

Control System

1-16

LIST OF COMPONENT FUNCTIONS

Name

Function

ECU

Engine-ECU

Uses the signals input from the various sensors to control operation of

actuators in accordance with the driving conditions.

Sensors

Ignition switch-IG

Detects the ON/OFF position of the ignition switch. When this signal

is input to the engine-ECU, power is supplied to components such as

the injectors, air flow sensor, idle speed control servo and crank angle

sensor.

Ignition switch-ST

Detects whether the engine is cranking. The engine-ECU controls the

fuel injection, throttle valve opening angle and ignition timing to the

appropriate settings based on this signal.

Air flow sensor

Detects the amount of intake air (volumetric capacity) by means of a

Karman vortex meter. The engine-ECU controls the basic injector drive

time based on this signal and on the engine speed.

Barometric pressure sensor

Detects the barometric pressure by means of a semiconductor

diffusion-type pressure sensor. The engine-ECU detects the vehicle’s

altitude based on this signal, and uses this to correct the fuel injection

amount so that the optimum air/fuel mixture ratio is obtained for that

altitude.

Oxygen sensor

Detects the concentration of oxygen in the exhaust gas by means of

zirconia and platinum electrodes. The engine-ECU judges whether the

air/fuel mixture ratio is at the optimum theoretical ratio based on this

concentration.

Intake air temperature sensor

Detects the temperature of the intake air by means of a thermistor. The

engine-ECU corrects the fuel injection amount to the correct amount

corresponding to the intake air temperature based on the voltage

output from this sensor.

Engine coolant temperature

sensor

Detects the temperature of the engine coolant by means of a

thermistor. The engine-ECU detects how warm the engine is based on

the signal from this sensor, and uses this to control the fuel injection

amount, idle speed and ignition timing.

Throttle position sensor

Detects the throttle valve opening angle by means of a potentiometer.

The engine-ECU controls the throttle valve and also determines the

optimum fuel injection for the vehicle’s degree of acceleration based

on the voltage output from this sensor.

Vehicle speed sensor

Detects the vehicle speed by means of a magnetic rheostatic element.

Camshaft position sensor

Detects the No. 1 cylinder compression top dead centre position by

means of a hall element.

Crank angle sensor

Detects the crank angle by means of a hall element. The engine-ECU

controls the injectors based on the signal from this sensor.

Alternator FR terminal

Detects the energising duty ratio of the alternator field coil.

Power steering fluid pressure

switch

Detects whether there is a power steering load present by means of a

contact switch.

A/C switch

Detects the ON/OFF condition of the A/C.

ENGINE -

Control System

1-17

Name

Function

Sensors

A/C load signal

Inputs the compressor drive state (low load/high load) to the

engine-ECU. The engine-ECU controls the A/C idle-up revolution

speed using this signal.

Intercooler water spray switch

(automatic)

Sprays water when certain driving conditions are satisfied.

Intercooler water spray switch

(manual)

Sprays water while the switch is being pressed by the driver.

Diagnosis control terminal

Notifies the engine-ECU that the MUT-II has been connected to the

diagnosis connector, and enables communication between the MUT-II

and the engine-ECU.

Actuators

Engine control relay

Turns the engine-ECU power circuit on and off.

Injector

Drives the fuel injection by means of drive signals from the

engine-ECU.

Ignition coil

(integrated power transistor)

Interrupts the ignition coil primary current in accordance with the

ignition signals from the engine-ECU, in order to generate a high

voltage for ignition.

Idle speed control servo

The throttle valve bypass air amount during idling and deceleration is

controlled with the signal from the engine-ECU.

Fuel pump relay 1

Supplies power to the fuel pump when the ignition switch is at the ON

position.

Fuel pump relay 2

Controls the supply of power to the fuel pump in accordance with the

signal from the engine-ECU.

Fuel pump relay 3

Controls the supply of power to the fuel pump when driving at low loads

and when driving at high loads, in accordance with the signal from the

engine-ECU.

Fan controller

Controls the smooth operation of the radiator fan in accordance with

the signal from the engine-ECU.

Condenser fan relay (HI)

Controls the condenser fan operation (high speed) in accordance with

the signal from the engine-ECU.

Condenser fan relay (LOW)

Controls the condenser fan operation (low speed) in accordance with

the signal from the engine-ECU.

Intercooler water spray relay

Controls the driving of the intercooler spray motor in accordance with

the signal from the engine-ECU.

Waste gate solenoid valve

Controls the supercharging pressure which acts on the waste gate

actuator in accordance with the signal from the engine-ECU.

Purge control solenoid valve

Controls the purge air flow amount which is introduced into the surge

tank in accordance with the signal from the engine-ECU.

EGR control solenoid valve

Controls the negative pressure which operates the EGR valve in

accordance with the signal from the engine-ECU.

Secondary air control solenoid

valve

Controls the pressure which is introduced into the secondary air valve

in accordance with the signal from the engine-ECU.

Fuel pressure control solenoid

valve

Controls the fuel pressure in accordance with the signal from the

engine-ECU.

ENGINE -

Control System

1-18

Name

Function

Actuators

Alternator G terminal

Controls the current generated by the alternator in accordance with the

signal from the engine-ECU.

A/C relay

Controls the A/C compressor operation.

Engine warning lamp

(check engine lamp)

Illuminates when a sensor malfunction is detected to warn the driver

of the problem.

Intercooler water spray lamp

Illuminates when the intercooler is being sprayed in accordance with

the signal from the engine-ECU.

Content .. 7 8 9 10 ..