Chery T21 2014 Service Manual page 168

06 - SQR484F ENGINE MANAGEMENT SYSTEM
1 - Canister
3 - Canister Solenoid Valve
5 - Camshaft Position Sensor (Intake)
7 - Camshaft Position Sensor (Exhaust)
9 - Exhaust VVT Control Valve
11 - Downstream Oxygen Sensor
13 - Crankshaft Position Sensor
15 - Electronic Throttle
17 - Electronic Accelerator Pedal
System Function
06
 Calculate air flow
ECM calculates air flow by the signals from air flow meter and then adjusts injection volume to make air-
fuel ratio meet the requirements of various operating conditions.
 Measure crankshaft position and engine speed
ECM determines crankshaft position and engine speed according to the signals from crankshaft position
sensor and accurately controls engine ignition and injection timing.
 Determine operating sequence of cylinders
ECM recognizes the top dead center of No.1 cylinder by camshaft position sensor, so as to determine the
operating sequence of cylinders.
 Fuel control
There are two modes of fuel control: closed-loop fuel control and open-loop fuel control. The closed-loop
fuel control can accurately regulate the air-fuel ratio of engine, thus effectively controlling emissions. The
open-loop fuel control is applied when engine is starting or warming up, or when a oxygen sensor is
malfunctioning.
 Ignition control
The ignition control system of engine adopts packet control.
 Knock control
When a knocking is detected by knock sensor, the system will calculate the ignition advance angle that
needs to be delayed or advanced according to current operating conditions and knock intensity and
adjusts ignition angle, thus avoiding or reducing knocking.
 Emission control
The three-way catalytic converter can convert engine exhaust gas into harmless gas and discharge it into
atmosphere. When engine temperature becomes normal after warming up, ECM will activate closed-loop
fuel control to correct air-fuel ratio, thus realizing the optimum conversion efficiency of three-way catalytic
converter.
 Three-way catalytic converter protection
The engine management system has the function to protect three-way catalytic converter. The ECM
estimates three-way catalytic converter temperature according to engine operating conditions. When it is
estimated that exhaust temperature will exceed the converter's maximum permissible temperature for a
long time, ECM will automatically activate the protection function of three-way catalytic converter to keep
the temperature normal.
 System voltage protection
When system voltage becomes extremely high due to charging system malfunction, engine management
system will activate the protection program to limit engine speed, thus avoiding damage to ECM and
battery.
4
06–
2 - Air Flow Meter
4 - Intake VVT Control Valve
6 - Ignition Coil
8 - Fuel Injector
10 - Upstream Oxygen Sensor
12 - Coolant Temperature Sensor
14 - Knock Sensor
16 - Engine Control Module (ECM)
18 - Electric Fuel Pump
Chery Automobile Co., Ltd.