Geely EC715 2009, Workshop Manual

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Due to the rapid development of modern science and
technology, High-Speed ECM can quickly analyze the driver's
intention and calculate the basic throttle opening parameter
values, based on the throttle pedal signal, the signal variation
and signal change rate. At the same time, ECM adjusts and
optimizes the throttle opening parameter, based on various
sensors input signal status, so that the system further
calculates the optimum throttle opening control parameters
and implements the actual throttle control. ECM sends the
output control signal to the ETC motor drive circuit to open the
throttle according to the calculated opening parameter, based
on the revised throttle opening and pre-determined control
strategy. Because of the high speed calculation, the system
enables the engine speed changes are smooth under transition
engine operating conditions. The whole control process only
requires a few milliseconds, achieving excellent vehicle
performance.
The application of automotive electronic technology makes the
electronic drive control valve assembly diagnosis difficult to use
conventional visual inspection method. In the event of
electronic controlled throttle body malfunction, the system
needs to provide a "Jolt-limited" function to allows the driver to
drive the vehicle to a repair station for repair.
"Jolt-limited" control has the following two kinds of control
modes
1. System is unable to control the engine power
ECM will limit the engine power output, and the system can
not control the throttle opening and closing. The throttle
opens to the system pre-determined position.
ECM will shut down the engine ignition output. At this time
ECM internal fault occurs, the system can not control the
engine torque output. The throttle body adjust the opening
to (zero bit) off status. The system will be fully turn off the
ignition control functions.
2. System can not monitor the driver's intention
ECM will limit the engine power output. At this point, the
system loses the ability to determine and monitor the
driver's intention. In order to prevent damage to the engine,
ECM will limit the engine power output and lower engine
power increment and velocity increment. When braking,
ECM will adjust the engine speed to idle speed and adjust
the throttle opening to the system pre-determined position.
ECM will force the engine working at idle running status.
When the system loses the ability to determine and monitor
the driver's intention, ECM will force the engine working at
idle running status, and the idle speed will be the default
speed.
2.12.3.2 ECM Controlled Fuel Supply System
1. Fuel Pump Control
When the ignition switch is turned on, the fuel pump will run for
2 s. At this moment, if ECM does not detect the engine speed
signal, fuel pump stops running. Once the engine rotates, ECM
detects the engine speed signal and then controls the fuel
pump running.
0.6 s after the engine speed signal is lost, or the anti-theft
device requests to shut down the fuel pump, the fuel pump
stops running.
2. Start-up Fuel Injection Control
The pre-injection only occurs once during a normal start-up
process, and the following conditions have to be met:
– Engine starts to running (ECM detects a valid engine speed
signal).
– Fuel pump relay pull-in
– Fuel pump running longer than the accumulator delay time
–
The pre-injection has not yet happened
Once all the above conditions are met, the pre-injection will
happen in all cylinders at the same time.
3. Fuel Injection Pulse Width Control
Fuel Injection
Calculation
Air Fuel Ratio
Manifold
Pressure
Intake Air
Temperature
Intake Air
Flow
Intake Air
Efficiency
Self Learn
Adjustment
Fuel Injection
Coefficient
Fuel Injection
Pulse Width
Voltage
Amendment
Intake Air Efficient
Compensation
Deceleration
Transition
Fuel Control
Intake Air
Temperature
FE02-8038b
2-594 Control System JL4G15-D Engine
EC718/EC718RV EC715/EC715RV 10/2009