Great Wall GW491QE, Руководство по обслуживанию

Страница: 89 / 222

EF.2-4 Delphi฀engine฀management฀system-MT20U฀system฀control
-Evaporating฀/exhaust฀/pollution฀control.
- Waste-gas฀exhaust฀control;฀post-processing฀by฀a฀three-way฀catalytic฀converter;฀and฀closed-loop฀fuel฀control฀by฀signal฀from
oxygen฀sensor.
-Protection฀function฀offered฀by฀three-way฀catalytic฀converter;
-When฀the฀electronic฀theft-prevention฀system฀has฀not฀received฀a฀correct฀password฀from฀the฀key,฀the฀computer฀control฀system฀will
not฀make฀fuel-injection฀or฀ignition,฀which฀prevents฀the฀engine฀from฀starting.
-Waste-gas฀exhaust฀control;฀post-processing฀by฀a฀three-way฀catalytic฀converter;฀and฀closed-loop฀fuel฀control฀by฀signal฀from฀oxygen
sensor.
-Protection฀function฀offered฀by฀three-way฀catalytic฀converter;
-Evaporating฀/exhaust฀/pollution฀control.
-Whereby฀the฀computer฀self-diagnosis฀function฀works฀abnormally฀on฀system฀parts฀&components,฀a฀fault฀indicator฀light฀may฀remind
user฀of฀inspection฀and฀repair,฀meanwhile,฀a฀bypass฀control฀program฀under฀emergency฀will฀be฀used฀to฀control฀the฀working฀of฀engine.
-Fault฀indication฀/communication฀function฀may฀be฀used฀for฀a฀two-way฀communication฀after฀the฀connection฀with฀the฀Fault฀Diagnosis
Instrument,฀and฀with฀PC฀computer.
Function฀of฀MT20U฀system:
-Starting฀control฀logic
-Ignition฀control฀logic
-Idle-speed฀control฀logic
-Knock฀control฀logic
-Accelerating฀/฀decelerating฀/฀fuel฀cut฀&overflow฀control฀logic
-Play฀&plug฀air฀conditioner฀control฀logic
-฀Carbon-canister฀solenoid฀valve฀control฀logic
-฀Temperature฀control฀logic฀for฀three-way฀catalytic฀converter
-Cooling฀fan฀control฀logic
-Mileage฀accumulation฀control฀logic
-Theft-detector฀control฀logic
-Whole-vehicle฀exhaust฀control฀logic
MT20U฀system฀control
1.฀Starting฀control
After฀the฀ignition฀switch฀is฀opened,฀fuel฀pump฀will฀run฀for฀1.5฀seconds,฀then฀stop.
Following฀the฀rotation฀of฀engine,฀the฀fuel฀pump฀will฀start฀to฀run฀when฀ECU฀detects฀tw o
valid฀58X฀signals
If฀the฀rotating-speed฀signal฀has฀been฀off฀for฀0.8฀second,฀or฀when฀fuel฀pump฀needs฀to฀be฀closed฀as฀required฀by฀the฀theft฀detector,฀the
fuel฀pump฀will฀stop฀running.
Start฀pre-injection the฀start฀pre-injection฀only฀acts฀once฀during฀a฀normal฀starting฀process.
Initial฀stage฀of฀starting฀process The฀inner฀pressure฀of฀inlet฀manifold฀is฀shown฀as฀ambient฀atmospheric฀pressure.฀When฀throttle
is฀closed,฀the฀idle-speed฀adjustor฀will฀have฀a฀fixed฀parameter฀changeable฀by฀the฀starting฀temperature.
During฀the฀starting:฀The฀fuel฀injection฀amount฀will฀vary฀depending฀on฀the฀change฀of฀engine฀temperature,฀and฀the฀ignition฀angle฀will
be฀adjusted฀respectively,฀and฀will฀vary฀depending฀on฀the฀change฀of฀engine฀temperature฀/฀inlet฀temperature฀/engine฀rotating฀speed.
Completion฀of฀starting The฀starting฀status฀will฀be฀ended฀when฀the฀engine฀rotating฀speed฀exceeds฀600r/min.
฀2.฀Ignition฀control฀logic
Coil฀magnetization฀control The฀magnetization฀time฀of฀ignition฀coil฀determines฀the฀ignition฀energy฀of฀spark฀plug.฀A฀much฀longer
magnetization฀will฀damage฀the฀coil฀or฀coil฀driver,฀while฀a฀much฀shorter฀magnetization฀will฀cause฀a฀fire.
Main฀ignition฀lead-angle When฀the฀engine฀water฀temperature฀is฀normal,฀the฀main฀ignition฀angle฀when฀throttle฀is฀open฀is฀usually
Min.฀ignition฀angle฀at฀best฀torque฀point฀(MBT),฀or฀knock฀critical฀point฀(KBL) When฀throttle฀is฀closed,฀the฀ignition฀angle฀shall฀be
less฀than฀MBT฀point฀to฀acquire฀a฀stable฀idle฀speed.
Modification฀to฀ignition฀lead-angle Modification฀to฀water฀temperature,฀modification฀to฀inlet฀temperature,฀modification฀to
altitude฀compensation,฀idle-speed฀modification,฀accelerating฀modification,฀modification฀to฀dense฀dynamical฀force,฀modification฀to฀oil-
cut฀when฀decelerating,฀modification฀to฀air฀conditioner฀control,฀and฀modification฀to฀waste฀gas฀re-circulation.
I dle-speed฀contr ol฀logic
Idle-speed฀control฀refers฀to฀a฀closed-loop฀control฀of฀system฀over฀the฀engine฀rotating฀speed฀when฀throttle฀valve฀is฀closed.฀T he฀idle
speed฀may฀be฀controlled฀by฀system฀through฀the฀adjustment฀of฀following฀parameters฀so฀that฀the฀actual฀rotating฀speed฀is฀consistent฀to
the฀desired฀idle฀speed
฀-Idle-speed฀air฀amount฀control
฀-Fuel-injection฀amount฀control
฀-Ignition฀timing฀control.
ProCarManuals.com