Geely EC718 2009 Workshop Manual page 669

Engine
2.12.2 Description and Operation
2.12.2.1 Overview
4G15D uses Delphi MT80 Engine Control System. Its main
characteristic is that the engine control module (ECM) is the
core system. The traditional mechanical throttle pedal and
mechanical throttle body are replaced by more advanced
electronic throttle acceleration pedal sensor assembly and the
electronic throttle body assembly. Due to adopt this system,
ECM control over the engine torque is more convenient. In
addition, MT80 control system also incorporates multi-point
sequential fuel injection, group direct ignition without electricity
distributions, variable valve timing control and three-way
catalytic converter processing, to meet the increasingly
stringent emission regulations.
System main functions includes:
1. Engine torque output control mode: ECM calculated the gas
flow through the intake air temperature sensor and intake
manifold pressure sensor signals, so that the Air-Fuel ratio
is closer to the current engine operating conditions
demand.
2. Torque control mode: ECM calculates the output torque
required and controls the engine output power, according
to the acceleration pedal position sensor signal.
3. Main relay control.
4. Close-loop control multi-point sequential fuel injection: A
close-loop fuel control can precisely control the engine Air-
Fuel ratio, therefore efficiently controls emissions. Close-
loop control can effectively eliminate the system and related
mechanical components
manufacturing error and improves vehicle consistency.
5. Variable Valve Timing (VVT) control: Variable valve timing
control system uses VVT actuator to change the intake
camshaft and the crankshaft relative positions. Engine
power management system calculates the best valve
timing based on engine operating conditions, and controls
VVT solenoid valve movement, allowing oil pressure, flow
and direction to change, and ultimately promoting the
camshaft movement to the desired position.
6. Fuel control without fuel return.
7. Fuel pump control.
8. ECM has built-in ignition drive module, without electricity
distinction group direct ignition.
wear and tear due
Control System JL4G15-D
9. Knock Control: When the knock sensor detects a knock
occurring, the system will calculate the ignition advance
angle delay based on the current conditions, knock intensity
and other necessary information, and defers the ignition
advance angle, so as to avoid or reduce knock. Electronic
Throttle Control: Since the system uses an electronic
throttle idle speed control, highly precise idle control can be
achieved. Such as the electrical load compensation, when
there are electrical loads or the load is cut off, due to a
sudden increase or decrease in engine load, resulting in
engine speed fluctuation in a certain range, this increases
the electrical load control adjustments. When the load
increases or decreases, the air flow rate and (or) the ignition
advance angle will be adjusted accordingly, so that the idle
speed remains steady.
10. Canister solenoid valve control
11. Cooling fan relay control
12. System self-diagnostic function: After the system enters
into working
components working, and tests them in real time. Once the
system or component malfunction occurs, the system will
light up the engine malfunction lamp to remind the driver to
repair or service the vehicle on time. In the mean time ECM
will start fault protection mode.
13. System voltage over load protection: When the charging
system malfunction causes the voltage too high, the system
will enter protection mode to restrict the engine speed to
prevent ECM damage.
2.12.2.2 Components Descriptions
to
1. Engine Control Module (ECM)
EC718/EC718RV EC715/EC715RV 10/2009
condition, ECM controls
2-587
all system
FE02-8031b