Maintenance Manual for J2 Sedan
Electronic Control System
of Engine
163
Section II Structural Principle and Inspection of Engine Control System
I.
System Description
Generally, the engine management system is mainly composed of three parts, namely sensors,
micro-processor (ECU), and actuators, to control the intake volume, fuel injection amount, and ignition
advance angle during the running of the engine. The basic structure is shown in the figure below:
Basic Structure of Engine Control System
In the engine electronic control system, the sensors are functioned as input parts to measure all kinds of
physical signals (temperature, pressure, etc.) and convert to corresponding electric signals, the ECU is
functioned to receive the input signals from sensors, calculate and process as per preset programs,
generate corresponding control signals, and output to power drive circuits, and the power drive circuits
execute different actions by driving corresponding actuators and control the engine to run as per preset
control strategy. At the same time, the malfunction diagnosis system of ECU monitors various
components and control functions in the system. Once a malfunction is detected and confirmed, the
system will save the malfunction code and activate the “Limp home” function. Upon the detection that
the malfunction is resolved, the system will resume to normal values.
The greatest characteristic in the electronic control system of the M7 engine is the adoption of
torque-based control strategy. The torque-based control strategy is mainly intended to link a great
amount of different control objectives. This is the sole method to integrate flexibly all kinds of functions
into different variants of ECU depending on the engine and vehicle models. The structural diagram of
the electronic control system is shown as below:
Engine
Actuators
Sensors
Diagnosis
Diagnosis
Product
manufactured by
UAES
Electric fuel pump ansd
brakckt assembly
Diagnosis
interface
Stepping
motor
Speed
sensor
Throttle position
sensor
Three-way
catalytic
converter
Oxygen sensor
Ignition
coil
Phase
sensor
F
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e
l
d
i
s
t
r
i
b
u
t
o
r
p
i
p
e
a
s
s
e
m
b
l
y
Fuel
pressure
regulator
Intake
pressure/
temperature
sensor
Fuel
filter
Fuel tank
Knock
sensor
Fuel injector
Water temperatrue
sensor
Carbon canister
control valve
Carbon canister
Throttle body assembly
